One of David Cameron's most important advisers is leaving Britain to live in the US for six months, the Sunday Telegraph reported.
Steve Hilton, the Tory leader's director of strategy, is credited as a mastermind of the party's revival over the last two years.
But the Telegraph disclosed that he was accompanying his wife, Rachel Whetstone, in a move to California this summer.
The Conservatives confirmed the development, but stressed that it was only temporary and that Mr Hilton's role would not change - despite the eight-hour time difference.
Whetstone, herself a former adviser to Michael Howard, Cameron's predecessor as leader, has been promoted to Google's vice president of global communications and public affairs.
They will live, with their young baby, close to Google's headquarters in Santa Clara County while Whetstone undertakes a six-month induction in her new post.
A party spokesman said Hilton would be "backwards and forwards" between London and California throughout the six months, after which they would return to the UK.
He added: "He's totally committed to David and the project of the modern Conservative Party. Nothing changes.
"It's not impossible to do the job Steve is doing for the party from out there, despite the time difference."
The Telegraph claims that Hilton has been a leading influence behind the Tories' public relations strategy of the last two years, with its emphasis on shedding the "nasty party" label and embracing issues such as the environment.

Dods Parliamentary Communications Ltd