Peter Mandelson has told the BBC that he will be staying in his post as EU Trade Commissioner until 2009.
The imminent change of British Prime Minister had raised the possibility that Mr Mandelson might be sacked as the UK’s Commissioner.
There is an EU Commissioner from every member state. Mr Mandelson has been the UK’s man in Brussels since November 2004.
He has very poor relations with Gordon Brown, the most likely successor to Tony Blair.
Mr Mandelson backed Mr Blair over his close friend Mr Brown for the leadership of the Labour party in 1994.
Mr Brown is said to have nurtured a grudge against Mr Mandelson ever since. The Prime Minister is expected to stand down in May.
Mr Mandelson told BBC Radio 4′s The World At One: “I don’t know whether this is going to come as a disappointment to him, but he can’t actually fire me.
“So like it or not, I’m afraid he will have to accept me as Commissioner until November 2009.
“But I will not be seeking a nomination for a further term after that time.”
Mr Mandelson has had a colourful political career. One of the architects of New Labour, he was one of Tony Blair’s closest advisers.
When Labour came to power in 1997, he was rewarded with the job of “co-ordinating the government,” in which he antagonised many more senior figures.
He was appointed to the Cabinet twice, but had to resign both times.
He was famously outed on national television by gay journalist Matthew Parris.
The press then took to reporting on his personal life with his Brazilian boyfriend, Reinaldo Avila da Silva.
Despite the animosity between Mr Brown and Mr Mandelson, the former spin doctor told the BBC that the Chancellor could work well in Europe as Prime Minister.
“I think he has the very real potential to be a constructive European, but it takes working at, and I’m sure he would be the first to acknowledge that,” he said.