Prince William and Catherine Middleton, the new Duke and Duchess of Cambridge, have left for their honeymoon, a spokesman for St James' Palace says.

More than a week after their April 29 wedding, the pair left the UK on Monday bound for an undisclosed location, the palace revealed.

The holiday location remains officially under wraps but British newspaper the Daily Mirror reports the newlyweds have touched down at a western Indian Ocean island hideaway in the Seychelles.

"We are not confirming and we are not commenting on speculation on where they may be going on their private honeymoon, we are just confirming that they have gone," a palace spokesman said on Tuesday.