Bush telephoned PM Gilani (above) to congratulate him on becoming premier after he won general elections last month. -- AFP

Spokeswoman Dana Perino said Bush telephoned Gilani to congratulate him on becoming premier after he and other opponents of President Pervez Musharraf - a key Bush ally in the war against terror - won general elections last month.

The US president 'said he looks forward to working with him and the new government of Pakistan,' Ms Perino told reporters about the phone call at 7.50 am (7.50 pm Singapore time).

'He reiterated that Pakistan is an important ally and country, and the two leaders agreed that fighting extremists is in everyone's interest,' Perino added.

Earlier on Tuesday, Mr Musharraf swore in Mr Gilani, a key aide of slain opposition icon Benazir Bhutto, as prime minister.

The United States, which now hesitates to call Mr Musharraf an indispensible ally in the war against Al-Qaeda and the Taleban, was following events closely as the election result raised questions about US-Pakistani relations.

US Deputy Secretary of State John Negroponte and Assistant Secretary of State Richard Boucher were visiting Pakistan to meet Mr Musharraf as well as the new political leadership, including former premier Nawaz Sharif and Mr Gilani.

Mr Sharif said he told Negroponte that the government would review Mr Musharraf's cooperation with the United States, saying he wanted to curb militancy but that he did not want the country to become a 'murder-house.'

His comments came amid US jitters over a New York Times report at the weekend that said that victorious political leaders intend to start negotiations with militants in the hope of ending recent violence.

US State Department spokesman Sean McCormack, when asked whether Washington could support negotiations with extremists rather than military action against them, said it was important to listen to the new government's views.

'Let's hear what they have to say first rather than try to play this game in public, that's the reason why the deputy secretary went there to talk to this new Pakistani government and political leadership, how they see the way forward,' Mr McCormack said.

Mr Negroponte also met with Musharraf, Mr McCormack said.

But he did not say whether Washington considered him indispensable when asked to repeat an adjective used here in the past.

'He's clearly an important person in Pakistani political life and he's done a lot of very positive things for his country and put them on an important course for its greater political and economic openness,' Mr McCormack said.

'Those are the kinds of questions that I think ultimately have to be answered by the Pakistani political system, but he remains somebody that we have worked with and will work with closely,' Mr McCormack said.

'He's a good friend and ally of the US,' he added.

Mr Musharraf, a general who seized power in a bloodless coup in 1999, became a key US ally after the September 11, 2001 attacks, siding with the United States against Al-Qaeda and the Taleban in neighbouring Afghanistan. -- AFP