There will be no royal wedding until 2013 for Prince William and his long-time girlfriend Kate Middleton, royal insiders said.

Last week, conclusions were made that the couple will announce their engagement after it was exposed that the royal diary had been "cleared" on June 3 and 4.

The Buckingham Palace did not release any statement, but insiders told Britain's Sunday Express that a royal wedding will not be held before 2013.

According to the sources, the diary is too loaded for a royal wedding, with Prince Philip's 90th birthday next year, the Queen's Diamond Jubilee, the London Olympics in 2012 and Prince William's military commitments that will end by spring 2013.

Announcements of royal engagements are usually done in the spring with a view to a summer wedding.

Prince William will turn 30 in 2013, the age when he wants to get married. Ms Middleton is 28.