Musharraf said on Saturday that former prime ministers Benazir Bhutto and Nawaz Sharif, who pose the biggest threat to his continued rule, should stay away to avert possible political turmoil in the country.

Benazir Bhutto's Pakistan People's Party (PPP) said any elections held in her absence could not be free and fair.

"Benazir Bhutto will come before elections. We have rejected Musharraf's call because elections cannot be free and fair in her absence," her spokesman Farhatullah Babar told AFP.

He said he expected Benazir Bhutto to return sometime between September and December. General elections are due late this year or early 2008.

Sharif's Pakistan Muslim League also rejected the call, insisting that "politicians do not create problems, they resolve the problems."

"General Musharraf is responsible for all the problems Pakistan is facing today and he should quit," said party spokesman Siddiqul Farooq, adding that Sharif may return in October.

The beleaguered president is facing a wave of Islamist violence across the country amid US accusations that Pakistan's border areas have become a safe haven for al-Qaeda and the Taliban.

Musharraf told newspaper executives Saturday that the return of the opposition leaders "would not be proper" if it were to lead to disturbances, adding that "stability should reign" until the vote.

Musharraf also said that no extreme steps, including the imposition of a state of emergency which he reportedly considered last week, would be taken by the government, Dawn newspaper reported.