Boris admits London will be real winner of Olympics, not regions

Government Ministers and Olympic officials have been desperate to insist the games – costing 9.3bn – will be good for the whole country, but the London Mayor pulled no punches as he was quizzed by staff at Asda headquarters.

"The answer is I'm afraid the benefit in terms of regeneration will be mainly concentrated in London, but that's not a bad thing because London's the motor of the economy, it drives consumption, it drives growth," he said.

"The other thing I'd mention is London taxpayers are paying 20 a head in Band D in their council tax for the privilege of the Olympics.

"I'm not going to pretend to you the Olympic afterglow is going to be great because I think that's trying incredulity."

Mr Johnson met shoppers in The Light shopping and leisure complex in the centre of Leeds before heading to Asda's headquarters where he sampled prize-winning cheese and tasted vintage champagne.

Addressing staff, he warned that a hung parliament would be bad for the country and the country needed a new start, warning that unless they voted Tory "there's a real risk old Gordon Brown will hang in there for another five years munching his fingernails and hurling his phones."

"I've been dispatched like Lenin in a sealed carriage all the way from London to Asda in Leeds to give you this message," he said.

Speaking to the Yorkshire Post at the end of his visit, Mr Johnson insisted the influx of tourists coming to Britain in 2012 for the Olympics was "not going to be a bad thing" for Leeds and the rest of Yorkshire and said there would not be a "zero sum gain".

But he stood by his right to bang London's drum and call for policies that favour the capital because the rest of the country would benefit from its successful economy as well.

"My job is to bang the drum for London," he said.

"That doesn't mean I don't love West Yorkshire and Leeds."

With the Tories promising a referendum for voters in Leeds on whether to install an elected mayor if they win the election, Mr Johnson said it was for the people of the city to decide although he said it was a model that worked well in London.

Asked about his arrival on the campaign trail in Yorkshire, he said: "Leeds is thought to be so critical – 'he who holds Leeds holds Britain' is the thinking of the Tory party at the moment.

"There are five seats that could go Tory and we're really confident and hopeful. We're throwing everything at it."