• Spain claims the British overseas territory of Gibraltar.
• Mauritius claims the entire Chagos Archipelago in the British Indian Ocean Territory, including the island of Diego Garcia used as a joint UK/US military base since the 1950s when the inhabitants were forcibly removed, Blenheim Reef, Speakers Bank and all the other features.
• Dispute over territorial waters and continental shelf rights around Rockall.There is a territorial claim in Antarctica, the British Antarctic Territory, which overlaps with areas claimed by Chile and Argentina.
• Conflicting claims over the Falkland Islands, controlled by Britain but claimed by Argentina. The dispute escalated into the Falklands War in 1982 over the islands' sovereignty, in which Argentina was decisively defeated.

Commonwealth of Nations & Ireland

The UK has varied relationships with the countries that make up the Commonwealth of Nations which originated from the British Empire. Elizabeth II of the United Kingdom is the head of the Commonwealth and is head of state of 16 of its 54 member states. Those that retain the Queen as head of state are called Commonwealth Realms. Over time several countries have been suspended from the Commonwealth for various reasons. Zimbabwe was suspended because of the authoritarian rule of its President[13] and so too was Pakistan, but it has since returned. Countries which become republics are still eligible for membership of the Commonwealth so long as they are deemed democratic. Commonwealth nations such as Malaysia enjoyed no export duties in trade with the UK before the UK concentrated their economic relationship with EU member states.

The UK was once a dominant colonial power in many countries on the continent of Africa and its multinationals remain large investors in sub-Saharan Africa. Nowadays the UK, as lead member of the Commonwealth of Nations, seeks to influence Africa through its foreign policies. Current UK disputes are with Zimbabwe over human rights violations. Tony Blair set up the Africa Commission and urged rich countries to cease demanding developing countries repay their large debts.

Australia


Australia – United Kingdom relations are close, marked by shared history, culture, institutions and language, extensive people-to-people links, aligned security interests, and vibrant trade and investment cooperation. The long-standing relationship between the United Kingdom and Australia formally began in 1901 when the six British Crown colonies in Australia federated, and the Commonwealth of Australia was formed as a Dominion of the British Empire. Australia fought alongside Britain in World War I, notably at Gallipoli, and again in World War II. Andrew Fisher, Australian prime minister from 1914 to 1916, declared that Australia would defend the United Kingdom "to the last man and the last shilling." Until 1949, the United Kingdom and Australia shared a common nationality code. The final constitutional ties between United Kingdom and Australia ended in 1986 with the passing of the Australia Act 1986.

Barbados


The two countries are related through common history, the Commonwealth of Nations and their sharing of the same Head of State, Queen Elizabeth II as their Monarch. As one of the first English colonies, the initial permanent European settlement took place in the early seventeenth century by English settlers. Barbados thereafter remained as a territory of the United Kingdom until it negotiated independence in 1966. In recent years, increasing numbers of British nationals have purchased secondary homes in Barbados, and the islands ranked as the Caribbean regions' fourth largest export market of the United Kingdom. The British High Commission was established in Bridgetown, Barbados in 1966 and there is also a Barbadian High Commission in London.

Canada


London and Ottawa enjoy cooperative and intimate contact, which has grown deeper over the years; the two countries are related through history, the Commonwealth of Nations, and their sharing of the same Head of State and monarch. Both countries fought together in both World Wars, the Korean War, and more recently cooperate in the coalition in the War in Afghanistan. Both are founding members of NATO, and also belong to the G7 (and the G8). Canada has been referred to as the "linchpin of the English-speaking world", by Winston Churchill, as it connects the three anglo countries. America, Britain, and Canada were the first countries to share the knowledge of the atom bomb together, as the three all worked on the Manhattan Project together.

Cyprus

The UK maintains two sovereign area military bases on the island of Cyprus. The UK is also a signatory to a treaty with Greece and Turkey concerning the independence of Cyprus, the Treaty of Guarantee, which maintains that Britain is a "guarantor power" of the island's independence.

Both countries are members of the European Union.

India

India has a high commission in London and two consulates-general in Birmingham and Edinburgh. The United Kingdom has a high commission in New Delhi and three deputy high commissions in Mumbai, Chennai and Kolkata. Both countries are full members of the Commonwealth of Nations. Since 1947, relations between the two countries have been mostly friendly and there are many areas in which both India and the UK seek stronger ties for mutual benefit.

Ireland

Despite a long history of conflict from English Tudor plantation in Ireland to the Irish War of independence, the UK presently works closely with the government of the Republic of Ireland in areas concerning the peace process in Northern Ireland as well as on many security issues. In 1949 the Irish Houses of Parliament passed the Republic of Ireland Act, making the Republic of Ireland officially fully independent; the country withdrew from the Commonwealth. Under the Ireland Act 1949 Irish citizens are treated as though they are Commonwealth citizens and not aliens for the purposes of law. Until 1998, the Republic of Ireland claimed Northern Ireland, but this was rescinded under the Belfast Agreement through an amendment of the Irish Constitution, which now states an aspiration to peaceful unity. There is an ongoing dispute that also involves Denmark and Iceland, over the status of the ocean floor surrounding Rockall. However, this is for the most part a trivial issue rarely makes it onto British-Irish meeting agendas.


Malaysia

The United Kingdom has a high commission in Kuala Lumpur, and Malaysia has a high commission in London. Both countries are full members of the Commonwealth of Nations. Both the UK and Malaysia are part of the Five Powers Defence Arrangements.

The Yang di-Pertuan Agong Sultan Abdul Halim of Kedah paid a state visit to the United Kingdom in July 1974. The Yang di-Pertuan Agong Sultan Azlan Shah of Perak paid a state visit to the United Kingdom in November 1993. HM Queen Elizabeth II of the United Kingdom paid state visits to Malaysia in October 1989, and in September 1998.

Malta


In the 1950s and 1960s, serious consideration was given in both countries to the idea of a political union between the United Kingdom and Malta. However, this plan for "Integration with Britain" foundered, and Malta gained its independence from the United Kingdom in 1964. British Monarch Queen Elizabeth II remained Queen of Malta until the country became a Republic in 1974. There is a small Maltese community in the United Kingdom. In addition, the British overseas territory of Gibraltar has been influenced by significant 18th and 19th Century immigration from Malta (see "History of the Maltese in Gibraltar").

Both countries are members of the European Union.

Nauru


Nauru was part of the British Western Pacific Territories from September 1914 and June 1921. The British Government had ceased to exercise any direct role in the governance of Nauru by 1968, when the island achieved its independence. The Nauruan government maintains an Hon. Consul, Martin W I Weston. The British High Commission in Suva is responsible for the United Kingdom's bilateral relations with Nauru.

New Zealand


Up to about the 1960s, New Zealand also had extremely close economic relations with the United Kingdom, especially considering the distance at which trade took place. As an example, in 1955, Britain took 65.3 percent of New Zealand's exports, and only during the following decades did this dominant position begin to decline as the United Kingdom oriented itself more towards the European Union, with the share of exports going to Britain having fallen to only 6.2 percent in 2000.Historically, some industries, such as dairying, a major economic factor in the former colony, had even more dominant trade links, with 80-100% of all cheese and butter exports going to Britain from around 1890 to 1940. This strong bond also supported the mutual feelings for each other in other areas.

Nigeria


Nigeria, formerly a colony, gained independence from Britain in 1960.

Pakistan


Pakistan was a colony of Britain from 1 November 1858 to 13 August 1947 as part of the Indian Empire. Both UK and Pakistan are active members of the Commonwealth of Nations.

Papua New Guinea


Papua New Guinea and the United Kingdom share Queen Elizabeth as their head of state. They have had relations since 1975 when Papua New Guinea gained independence from Australia.

Singapore

Singapore and the United Kingdom share a friendly relationship since Singapore became independent from the United Kingdom in 1959. Singapore retained the Privy Council as the final court of appeal up till 1989 (fully abolished in 1994) due to political reasons.

United States

The United Kingdom and the United States are close military allies. The two countries share cultural similarities, as well as military research and intelligence facilities. The UK has purchased military technology from the USA such as Tomahawk cruise missiles and Trident nuclear missiles, and the US has purchased equipment from Britain (e.g. Harrier Jump Jet). The USA also maintains a large number of military personnel in the UK. In recent years, the Prime Minister of the United Kingdom and the President of the United States have often been close friends, for example Tony Blair and Bill Clinton and later with George W. Bush and in the 1980s the often like-minded Margaret Thatcher and Ronald Reagan. Present British policy is that the relationship with the United States represents Britain's "most important bilateral relationship".

Europe

The UK has had good relations with the rest of Europe since the Second World War. It became a member of the European Economic Community in 1973, which eventually evolved into the European Union through the Maastricht Treaty twenty years later. Although the UK does not use the Euro and is not a member of the Eurozone, it still plays a leading role in the day to day workings of the EU.

Britain has a century-long alliance with France, through the Entente Cordiale, which was reconfirmed through the November 2010 Defence and Security Co-operation Treaty – setting up a joint expeditionary force, aircraft carrier sharing and nuclear collaboration – as well as extremely close cooperation with France over the 2011 Libyan Uprising and Libyan no-fly zone.