Scotland Yard are to "bring their expertise" to the search for Madeleine McCann after a personal request from the Prime Minister.
A Home Office spokesman said: "The Prime Minister and the Home Secretary have today agreed with Sir Paul Stephenson that the Metropolitan Police will bring its particular expertise to this case."
The spokesman added that the Government hopes Scotland Yard can bring a new perspective to the case and the Home Office will be providing "the necessary financial support".
He went on: "The Government's primary concern has always been and remains the safe return of Madeleine.
"Although she disappeared in Portugal, and the Portuguese retain the lead responsibility in the case, law enforcement agencies here have continued to follow up leads and pass information to the Portuguese authorities as appropriate."
He added that it would not be appropriate to discuss details at this stage.
The move comes after Kate and Gerry McCann hit out at the actions of the Home Office, saying it had offered "words, but no action" to assist them in the investigation.

Why not just ask the parents to admit they killed their daughter with an accidental overdose ?