It was a coup for Peter Fincham to announce at the BBC One season launch that the comedians Matt Lucas and David Walliams had signed an exclusive three-year BBC deal said to be worth £6 million.

But that was July last year and while the Little Britain duo have enjoyed global success, there is still no sign of the new BBC show that was promised to viewers. The award-winning pair yesterday announced a new series – but the six-part sketch show is being made by the HBO cable channel for American viewers. The US show, which follows the pair’s extensive tour of Australia, will be filmed in the autumn, delaying their return to British screens for another six months at least.

“The new series will be a sketch show set in contemporary America,” explained Walliams. “We are taking some existing characters and writing new material for them, as well as introducing new characters and ideas.”

Mr Fincham, the underfire BBC One Controller, admitted that licence-fee payers had yet to see the fruits of the deal. He said: “They will make a new series for BBC One but it’s taking a little longer than we had hoped because they are so busy.”

Lucas and Walliams will not be paid the full value of the first year of their deal, BBC sources said. Under their contract, the duo must produce a certain number of hours of “comedy/ entertainment” for the BBC over a three-year period. Their final earnings could be far less than £6 million, but the contract allows the duo to sell the Little Britain format abroad.

The BBC Trust has announced a review into the salaries of the BBC’s top-earning stars, following criticism of Jonathan Ross’s £18 million deal. The review is expected to examine the obligations to deliver value-for-money under such deals.

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