A transport expert has been chosen by the Labour Party to fight Zac Goldsmith in the by-election he triggered by resigning in protest over Heathrow.
Christian Wolmar, who has written books on railway history, will stand for election in the Richmond Park contest on December 1.
The Tories are not putting up a candidate against Mr Goldsmith, who is standing as an independent, while the Liberal Democrats are hoping to snatch it back.
The Green Party has said it would not put up a candidate, leading senior Labour figures to urge the leadership to stay out, giving the Lib Dems a clear opening to take it.
But the local party picked Mr Wolmar, who has worked at Shelter and Camden Council.
He said: "It's a great honour to be selected to stand for Labour in the Richmond Park by-election which gives us an opportunity to expose the disastrous policies of this government and fight the third runway at Heathrow which I have long opposed.
"The Liberal Democrats and Zac Goldsmith supported every terrible decision taken by the last coalition government, from austerity to the unnecessary and expensive top-down reorganisation and creeping privatisation of the NHS. The Lib Dems are not a progressive alternative, but Labour is.
"Zac Goldsmith played a key role in the Leave campaign which led to the decision to take us out of the EU - a decision that 72% of voters here opposed. The only way to send a message to this government and that we do not accept what they are doing to our country is to vote Labour."