Ms Bhutto has filed nominations from two other constituencies, and has yet to hear whether they will be accepted.

"Even if they reject my two other applications I will challenge the decisions... I will continue to fight the military establishment to restore democracy in Pakistan," she told the BBC.

Ms Bhutto, who has been premier twice before, has been convicted of failing to answer corruption charges in court, and was thus ruled ineligible as a candidate in the polls.

I am happy for Nawaz Sharif that he has been allowed to run... I think they are trying to divide the opposition. But let me tell you the opposition will remain united against the military governmen

Benazir Bhutto

But on Thursday, officials accepted the nomination filed by another convicted former prime minister, Nawaz Sharif.

Both Mr Sharif and Ms Bhutto are living in exile outside Pakistan after the 1999 military coup.

General Musharraf has made clear he doesn't see any place for them in Pakistani politics, accusing them of having "looted" the country.

Supporters angry

Benazir Bhutto, the first woman to lead a Muslim nation, had filed papers to contest from her family's traditional stronghold in Larkana, in the south.

"She has been convicted by the anti-graft court, therefore she is not qualified to contest the elections," the AFP news agency quoted election commission official Akhlaq Hussain Ladak as saying in Larkana.

But Ms Bhutto's lawyers said the decision showed double standards.

Musharraf says he is strengthening democracy

"The verdict speaks of double standards set by the Pervez Musharraf Government. They accepted Nawaz Sharif's nomination who has also been convicted but rejected Ms Bhutto's. We will continue our legal and political fight against such moves, " one of Ms Bhutto's lawyers Ayaz Soomro told the BBC.

Hundreds of Bhutto supporters gathered outside the returning officer's court reacted angrily, shouting slogans against the country's military ruler, Pervez Musharraf.

Officials said on Thursday Mr Sharif's candidacy could still be blocked if appeals are filed against him by 6 September.

But if it goes unchallenged, Mr Sharif would be one of the most prominent politicians taking part in the general elections.

There are two laws which stand in the way of Mr Sharif and Ms Bhutto's political ambitions: one which bars candidates with criminal convictions, and another brought in by President Musharraf preventing former premiers from serving a third term.

Elections

The Election Commission's acceptance of Mr Sharif's nomination came as a surprise.

There is no word yet from the government but it is allowed to appeal against Mr Sharif's nomination to an election tribunal in the Lahore High Court until 6 September.

Both Mr Sharif and Ms Bhutto filed nomination papers in defiance of the law barring them.

General Musharraf, who overthrew Mr Sharif in a bloodless coup in October 1999, says he has called elections to restore democracy in Pakistan.

But many people have raised doubts over his intentions - particularly after he made sweeping changes to the constitution.

Critics say his new powers are intended to maintain General Musharraf's grip on authority - despite the elections.