Although the law allows the Mayor to also serve as an MP, both men have said they would want to devote their “full” attention to the mayoralty and tackling London’s problems.
Former mayor Ken Livingstone served in both roles for 13 months following his election as mayor in May 2000, only stepping down as MP for Brent East in June 2001.
At the time of his election as mayor in May 2008, Mr Johnson was the MP for Henley but quit the role the following month. He re-entered the Commons at last year’s general election, securing himself a continued place in frontline politics after his term as mayor ends in May.
The decision to split his attention between City Hall and Parliament prompted criticism from political opponents, including Mr Khan, who labelled him a “part-time mayor” and accused Mr Johnson of putting his career above Londoners’ needs.
However the Mayor and his supporters insist he uses his dual mandate to lobby ministers and speak up for London.
Appearing on LBC’s mayoral debate Goldsmith, who represents Richmond Park, confirmed he would “step down immediately” adding “you can’t do both jobs for a significant period of time.”
Asked by host Nick Ferrari whether he’d quit the Commons, Tooting MP Mr Khan answered “yep” but didn’t say when.
However after the show a campaign aide told MayorWatch that he would “do so as quickly as possible consistent with doing the right thing by his Tooting constituents”.
Since 2008 a mayor who also serves as an MP loses two-thirds of their City Hall salary, a rule which saw Mr Johnson’s City Hall pay fall from £143,911 to just £47,970 when he was elected MP for Uxbridge and South Ruislip last year.
Even with his parliamentary salary taken into account Mr Johnson’s salary for his final year in office is still significantly below his previous earnings, totalling £115,000.
Londoners will elect a new Mayor and the 25 members of the London Assembly on May 5th. Candidates for Mayor include Conservative Zac Goldsmith, Labour’s Sadiq Khan, Liberal Democrat Caroline Pidgeon, the Green party’s Sian Berry and UKIP’s Peter Whittle.
