Factbox: World leaders congratulate new UK PM David Cameron

World leaders contacted Britain's new centre-right prime minister David Cameron on Tuesday to congratulate him after he took over from Labour's Gordon Brown.

Here are brief details of their messages:

US president Barack Obama
President Obama phoned Cameron to congratulate him within an hour of him taking office.

Obama said he told Cameron he remained committed to a "special relationship" between their countries and invited him to visit Washington this summer.

"The United States has no closer friend and ally than the United Kingdom, and I reiterated my deep and personal commitment to the special relationship between our two countries -- a bond that has endured for generations and across party lines, and that is essential to the security and prosperity of our two countries and the world," Obama said in a statement.

German chancellor Angela Merkel
Chancellor Merkel phoned to offer her congratulations and invite Cameron to Berlin at the earliest opportunity, Cameron's Downing Street office said.

"They briefly discussed the world economy and the common European agenda," the statement said.

French president Nicolas Sarkozy
"The president offers his hearty congratulations to David Cameron on his appointment to the post of prime minister of the United Kingdom," said a statement from the Elysee Palace.

"He (the president) offers his best wishes for success ... And he hopes to work with him to reinforce the tight cooperation and the exceptional ties connecting France and the United Kingdom."

The statement went on to say that only by working together would the two countries be able to make their voice heard and work effectively whether for global security, to overcome the financial crisis  and to tackle climate change.

Canadian prime minister Stephen Harper
"On behalf of the government of Canada, I am pleased to offer my sincere and heartfelt congratulations to David Cameron on his general election victory in the United Kingdom and his appointment as prime minister by Her Majesty the Queen," Harper said in a statement.

"Our two countries share a deep and enduring relationship, forged in good times and bad by hundreds of years of shared history, values and tradition.

"We are united by the cause of freedom, democracy, human rights and the rule of law in both our respective countries and throughout the world. I am certain that the bonds between our two countries will deepen over the coming years."