UXBRIDGE and South Ruislip MP John Randall has announced he will not stand at the 2015 general election.
Westminster commentators are now seeing it as an ideal route for a Commons return by London Mayor Boris Johnson.
Sir John, who was elected with a 11,216 majority in 2010, informed his Conservative association of his decision last night.
“It’s been a privilege and honour,” he said of his 17 years representing the constituency.
He says he has no idea who will be his successor but understands the inevitable speculation surrounding Mr Johnson.
The Mayor, whose term runs to 2016, would be allowed to continue at City Hall at the same time as serving as an MP.
He has been linked with a series of safe Conservative seats but continues to duck requests to declare his intent to stand in 2015 or in a by-election.
Last night, the Press Association was reporting that suggestions of him seeking to fight the 2015 election from Uxbridge were "nothing more than speculation and rumour around another vacant seat".
Sir John, 57, a former Conservative deputy chief whip, who still lives in the heart of the constituency, says he does not plan to retire but is considering fresh challenges.