KABUL – Afghan President Hamid Karzai's main rival Abdullah Abdullah staged a rally of village elders on Tuesday to denounce fraud in last month's election and said he was doing all he could to keep his supporters off the streets.

Abdullah has accused Karzai's government of stuffing ballot boxes on a massive scale and has lodged hundreds of allegations of fraud in the August 20 ballot.

With about half of votes tallied so far, partial results show Karzai maintaining a lead over Abdullah, although still without the outright majority needed to avoid a potentially destabilizing run-off in October. Final results are due later this month.

In a packed hall in central Kabul, 300 tribal elders dressed in flowing white robes shook fists and delivered emotional speeches as they urged Abdullah to take action against what they described as widespread electoral violations.

Addressing them from a stage flanked by armed guards, Abdullah vowed to protect their votes, but urged restraint.

My main concern today is that there is a lot of pressure from the people on me (to hold) demonstrations, Abdullah told Reuters on the sidelines of the meeting.

Kandahar wants to do demonstrations. Khost wants to do demonstrations. Ghazni wants to do demonstrations. And I have to stop them, he said, referring to cities in the violent south and east where he says fraud was its worst.

I ask them for calm, I ask them for patience.

Most votes have yet to be counted in the Pashtun south, Karzai's main support base. Those votes could yet tip the balance in favor of a first-round victory for Karzai, but some of those votes could be thrown out if Abdullah's complaints are upheld.

The election was a major test for Karzai after eight years in power and for U.S. President Barack Obama's new regional strategy to defeat the Taliban and stabilize Afghanistan in the face of recent gains by insurgents.

An independent fraud watchdog, the Election Complaints Commission, is investigating almost 2,500 allegations of abuse, including 567 it says are serious enough to affect the outcome.

Three of the commission's five members are United Nations appointees.

Abdullah's main support base is among Tajiks in the north but Tuesday's gathering included elders from southern regions, where he has made an effort to show he has support.

We do not agree with this election. We must unite hand in hand and think of a better government, said one elder, Haji Manan, from Helmand province, a Taliban stronghold.

In my district, nobody went to polling stations to cast ballots for any candidate on election day. But now 20,000 boxes are full of votes in favor of Karzai.

Karzai has not commented on fraud allegations.

Abdullah has said he will reject the result if he believes fraud played a part in the outcome, although he has played down suggestions of civil unrest.

I can ask for action that is constitutional and peaceful at some stage, he said. But at this stage I will wait until the election complaints commission completes its job.

(Editing by Paul Tait)

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