Andrew Dismore, Labour’s former Hendon MP, has said he will not stand in the constituency in June’s general election for “personal reasons”.
Mr Dismore was first elected as MP in 1997, but lost his seat to Conservative Matthew Offord in 2010 by just 106 votes.
His bid to regain the seat – which has the second largest proportion of Jewish voters in the country – in 2015 ended in a second defeat to Mr Offord, by 3,724 votes.
Mr Dismore, currently a Greater London Assembly member for Barnet and Camden, said he was not in a position to give “100 per cent commitment” to this year’s campaign.