David Cameron arrived at Buckingham Palace tonight to accept an invitation from the Queen to form a new government.

It followed the dramatic announcement by Gordon Brown that he was standing down, bringing down the curtain on 13 years of Labour rule.

After five days of uncertainty, Mr Brown finally accepted that he was unable to form a coalition with the Liberal Democrats.

Mr Cameron arrived at the Palace around an hour after Mr Brown conceded defeat and drove to Buckingham Palace to tender his resignation as Prime Minister to the Queen.

Moments after Mr Brown acknowledged the game was up, Liberal Democrat and Conservative negotiators emerged from the Cabinet Office after five-and-a-half hours of talks in which they appear to have reached agreement on a coalition government.

Speaking outside No 10, with wife Sarah by his side, Mr Brown said: "I wish the next prime minister well as he makes the important choices for the future.

"Only those who have held the office of prime minister can understand the full weight of its responsibilities and its great capacity for good.

"I have been privileged to learn much about the very best in human nature and a fair amount too about its frailties, including my own."

The Prime Minister stressed, as he left Downing Street: "I loved the job, not for its prestige, its titles and its ceremony, which I do not love at all.

"No, I loved the job for its potential to make this country I love fairer, more tolerant, more green, more democratic, more prosperous, more just - truly a greater Britain."

Mr Brown announced that he would stand down as Labour leader with immediate effect.

Even as Mr Brown was whisked off to the Palace, speculation began about the extent of the Conservative-Lib Dem co-operation, with expectations high that Nick Clegg's party has been guaranteed seats in a cabinet led by Mr Cameron.

Following his trip to the Palace, Mr Brown visited Labour HQ, where he was greeted by cheers and applause.

He announced that his deputy Harriet Harman was taking over as acting Labour leader until his successor is chosen.

Mr Cameron is now tasked with forming his cabinet and getting on with the business of government, following a day of predictably high drama at Westminster which always seemed to have only one end.

Mr Brown sought to bring a soft-focus family end to his time in Downing Street by walking towards his limousine with his small children, John and Fraser.

But hard politics interrupted, with a Lib Dem spokesman accusing Labour of failing to engage seriously in talks over a possible "progressive alliance" earlier in the day.

"It is clear that the Labour Party never took seriously the prospects of forming a progressive, reforming government with the Liberal Democrats," said the spokesman.

"Key members of Labour's negotiating team gave every impression of wanting the process to fail and Labour made no attempt at all to agree a common approach with the Liberal Democrats on issues such as fairer schools funding for the most deprived pupils and taking those on low incomes out of tax."