Former Cabinet minister Stephen Byers is to stand down from Parliament at the next general election, he announced today.
Mr Byers is one of the most prominent Blairites on the Labour backbenches and has been a critic of Gordon Brown's performance as Prime Minister, openly discussing the prospect of challenges to his leadership.
Today, he said he was standing down as MP for North Tyneside "in order to pursue other interests and look to fresh challenges", but insisted that he would continue to support Labour in the months and years to come.
Mr Byers, 56, entered Parliament as MP for Wallsend, in Labour's stronghold of North East England, in 1992 and switched to North Tyneside after boundary changes in 1997. He had previously been elected to North Tyneside Council in 1980, rising to become deputy leader of the Labour-held council from 1985-92.
He served as schools minister after Labour won power in 1997, joining the Cabinet as Chief Secretary to the Treasury in 1998, moving to Trade and Industry Secretary later that year, then becoming Secretary of State for Transport, Local Government and the Regions after the 2001 election.
He resigned from the Government in 2002 in the wake of rows over his adviser Jo Moore's suggestion that the September 11 terror attacks made it "a good day to bury bad news".
On the backbenches, he became part of a small but high-profile group of Blairite ex-ministers, including Alan Milburn and Charles Clarke, who pushed for the Government to stick to New Labour policies.
Earlier this year, leaked details of MPs' allowances showed that he claimed £125,000 in second home expenses over five years for a flat wholly owned by his partner.
Mr Byers announced his decision to stand down at the monthly meeting of the North Tyneside Labour Party this morning, saying: "By 2010 I will have held elected positions as an MP and councillor for 30 years. That's over half my life and is a long time - especially in modern politics.
"For me this is the right moment to move on in order to pursue other interests and look to fresh challenges.
"I am proud to have served the people of North Tyneside as their MP since 1992. I have always tried to do my best for them. They are great people and I feel very fortunate to have been given the opportunity to represent them in Parliament.
"It has been a privilege to have served as a Cabinet minister in a Labour Government. This is something I will always be grateful for.
"During my time as an MP, I have always been ready to argue for the policies I believe in. I know that at times some of my ideas have not been easy for Labour Party members in North Tyneside. Despite this they have always given me their full support. I want to take this opportunity to give them my sincere thanks.
"It is clear to me that only the Labour Party has the answers to the challenges we face as a country. In what will now be a different role, I shall do all I can to support the party in the months and years ahead."
Mr Byers had a majority of 15,037 in the 2005 election, making North Tyneside a highly desirable safe seat for would-be Labour candidates.