London Evening Standard/London

Labour big-hitter Alan Johnson has ruled himself out of the contest to be London’s next mayor.

Instead the former home secretary said he would like to return to Labour’s frontbench after the 2015 general election.

Speaking in this month’s Total Politics magazine the Westminster heavyweight also launched a scathing attack on Boris Johnson, saying he lacked the “necessary skills” to be prime minister.

Asked whether he would run for mayor the Labour MP said: “I’m ruling it out. No. I seriously considered it in 2010. Now I’ve absolutely made up my mind. I’m going to stand for Hull West and Hessle as a member of parliament and I wouldn’t do that in 2015 if I was going to run for mayor in 2016.”

Johnson, who was Ed Miliband’s first shadow chancellor, was a favourite for Labour’s mayoral candidacy. His decision leaves the contest wide open.

Other potential candidates include former Olympics minister Tessa Jowell and Lord Adonis, a former transport and education minister known as the architect of the academies programme.

Comedian Eddie Izzard and Tony Blair’s former director of communications Alastair Campbell could also be in the running, along with London MPs Diane Abbott, David Lammy and Stella Creasey and former MP Oona King.

Johnson said it was “madness” how his party ran its selection last time, which ended with Ken Livingstone being chosen.

But he warned the Conservative mayor that whoever secures the Labour candidacy for 2016 would give him “substantial opposition”.

Attacking Johnson, he said: “I don’t think he would look the part as prime minister by the way. I think mayor of London is about as good as it gets for him, and I don’t think if he came into Parliament he would cut it as a minister.”

He added: “I just don’t think he’s got the necessary skills to do that. He’s got the skills to be the mayor because it’s very much kind of a ceremonial role and he’s good at that.”