On David Cameron being appointed as Prime Minister of the United Kingdom after coalition talks between his Conservatives and the Liberal Democrats concluded on 11 May 2010 , President Obama was the first foreign leader to offer his congratulations . Following the conversation Obama said : Foreign Secretary William Hague responded to the President 's overture by making Washington his first port of call , commenting : " We 're very happy to accept that description and to agree with that description . The United States is without doubt the most important ally of the United Kingdom . " Meeting Hillary Clinton , Hague hailed the Special Relationship as " an unbreakable alliance " , and added : " It 's not a backward-looking or nostalgic relationship . It is one looking to the future from combating violent extremism to addressing poverty and conflict around the world . " Both governments confirmed their joint commitment to the war in Afghanistan and their opposition to Iran 's nuclear programme
coalition talks
2010 United Kingdom government formation
Special Relationship