Zardari is convinced that if he and Sharif visited Washington and met top US officials to discuss Musharraf's fate, they might get "quick and desired results", The News daily quoted sources as saying.

Such a move would end the prolonged deadlock between the two main partners in Pakistan's ruling coalition over the issue of impeaching Musharraf and reinstating the judges sacked by the President during last year's emergency.

Zardari's move has come in the wake of Sharif's statement two days ago that the next round of talks between the PPP and the PML-N would be the "final" effort to resolve differences between the two parties.

Sharif has not specified what he intends to do if the talks do not produce any results.

The sources, however, said the PML (N) leader was "not interested in the proposal as he was fed up with the recent political somersaults of Zardari".

The PML-N, which pulled its ministers out of the cabinet in May after the Pakistan People's Party-led government failed to reinstate the deposed judges, has been hinting that it might part company with Zardari if he fails to deliver on his pledges to restore the judges and impeach the President. The sources said this was the second time that Zardari has tried to convince Sharif to accompany him on a foreign trip in a bid to achieve common political and economic goals.

Earlier, Sharif had rejected an invitation to accompany Zardari and Prime Minister Yousuf Raza Gilani to Saudi Arabia.

The sources said Zardari's fresh request is likely to meet the same fate as Sharif had "lost trust in promises and commitments made by Zardari and was in no mood to oblige the PPP leader".

Explaining the reasons for this, the sources said Sharif was "not interested in the proposal as he was fed up with the recent political summersaults of Zardari".

The sources said Zardari believed that the US is still backing Musharraf because of his role in the war on terror over the past eight years.