ISLAMABAD: Former Pakistan premier Benazir Bhutto's party fielded a presidential candidate against Pervez Musharraf on Wednesday, saying that the military ruler was no longer capable of tackling Al-Qaeda.
The embattled General Musharraf, a key US ally in the "war on terror", now faces two rivals in the polls on October 6, dashing his hopes of winning a second five-year term as president unopposed.
Pakistan's Supreme Court meanwhile is hearing opposition legal challenges arguing that Musharraf is ineligible for the election while he remains army chief, with a decision expected imminently.
Bhutto, who is set to return from self-exile next month, piled on pressure when she said that her Pakistan People's Party was nominating its vice chairman, Makhdoom Amin Fahim, to stand against Musharraf.
"We are doing this because we want to put ourselves in a better position to have more options. The issue of General Musharraf's legitimacy is foremost in the minds of Pakistani people," she said in Washington late on Tuesday.
Musharraf has enough support in Pakistan's current parliament to win.
But Bhutto, who has been in on-off power sharing talks with Musharraf from her exile in Dubai and London, said that if the Supreme Court rejects his nomination any official candidate has a chance.
"We do not want to leave the field open for General Musharraf. We don't want him to be elected unopposed," Nazir Dhoki, a party spokesman in Islamabad, said.
The spokesman said Fahim was expected to file his nomination papers on Thursday, the deadline set by the Pakistan election commission.
Other opposition parties have vowed to blockade the commission to prevent Musharraf from submitting his nomination, a vow that has prompted the arrests of more than 100 anti-Musharraf activists.
Musharraf, who seized power in a 1999 coup, raised fears that he could impose martial law on Tuesday when he declared that he would stay on as army chief if he is not re-elected.
The United States has urged him to hold free and fair elections and criticised the arrests earlier this week, but has largely backed Musharraf because it sees him as crucial to tackling Al-Qaeda.
Bhutto however said that under President Musharraf, Pakistan had become "the petri dish of the international extremist movement" and that only a new government with broad support could root out Islamic militancy.
Fighting the Taliban and Al-Qaeda "requires a national effort that can only flow from legitimate elections," she said on Washington's Capitol Hill, appealing to the US to drop its deep-pocketed backing for Musharraf.
The US has provided Pakistan with more than 10 billion dollars in aid since 9/11, most of it military.
Bhutto, who was twice prime minister in the 1990s, said she expected a warm welcome from supporters when she flies into Karachi, Pakistan's biggest city, on October 18.
"I hope for the best, and prepare for the worst," Bhutto said.
Musharraf instantly deported former prime minister Nawaz Sharif -- the man he toppled eight years ago -- when Sharif attempted to return home from exile earlier this month.
Bhutto also said Tuesday that if returned to power, she would allow UN inspectors but not Western powers to question Abdul Qadeer Khan, the father of Pakistan's nuclear bomb.
Musharraf has refused to grant any access to US officials eager to question the scientist since he admitted to passing atomic secrets to Libya, Iran and North Korea in a televised confession in February 2004.
