Boris Johnson is to renounce his American citizenship, removing a possible obstacle to becoming British Prime Minister.
The Mayor of London has dual nationality because he was born in New York, but says he wants to hand back his American passport.
"The reason I'm thinking I probably will want to make a change is that my commitment is, and always has been, to Britain," he told the Sunday Times during a week-long tour in the States.
"It's an accident of birth that has left me with this thing. I've got to find a way of sorting it out."
Mr Johnson - who is running for parliament in Uxbridge and South Ruislip - said he would discuss the matter with US ambassador Matthew Barzun.
"It is a laborious business. They don't make it easy for you," he added.
Constitutional experts say dual nationality is not a technical barrier to Mr Johnson becoming prime minister, but it is thought he would face scrutiny about his loyalties.
Aides said the mayor's priority was to avoid paying more tax to US authorities, after he was recently forced to settle a large capital gains tax bill.
