KABUL - The Taliban called on Afghans on Saturday to boycott next month's presidential election run-off and vowed to disrupt voting in a repeat of their threat to derail the disputed first round.

Election officials are hastily trying to prepare for the November 7 run-off, which removed one stumbling block for U.S. President Barack Obama as he weighs whether to send more troops to Afghanistan to fight a resurgent Taliban.

The Islamic Emirate of Afghanistan once again urges their respected countrymen not to participate, the Taliban said in a statement, emailed to Reuters, saying the election process was being orchestrated by Washington.

In order to make this process fail all the mujahideens will carry out operations on the enemy's centres, it said of the thousands of polling stations to be set up for the vote between President Hamid Karzai and challenger Abdullah Abdullah.

Karzai agreed to the vote after heavy international pressure.

A U.N.-backed fraud investigation invalidated thousands of his votes from the August 20 first round, pushing him below the 50 percent mark needed to avoid a run-off against Abdullah, his former foreign minister.

The Taliban also threatened to disrupt the first round but, despite sporadic attacks against candidates, election officials and polling stations, the austere Islamists failed to disrupt the process entirely.

However security fears contributed to a low voter turnout, especially in Taliban strongholds in the south and east. Election officials have said they expect turnout to be even lower for the run-off.

The Taliban, who ruled Afghanistan from 1996 until ousted by U.S.-backed Afghan forces in 2001, have strengthened their insurgency, with 2009 the deadliest year of the eight-year war.

Election officials have warned that NATO and Afghan security forces are not allowed themselves enough time to secure polling centres for the run-off.

The approach of Afghanistan's harsh winter, when much of the mountainous country becomes inaccessible, makes organizing and conducting the new poll even more difficult.

ROADS WILL BE BLOCKED

Official campaigning kicked off on Saturday afternoon but Karzai and Abdullah are not expected to start their rallies until later in the week.

Many Afghans have expressed disillusion about the election and whether to turn out.

The latest Taliban statement told Afghans not to leave their homes on polling day and said those who took part in the election would do so at their own risk.

The people must not take part in the elections ... all the main roads will be blocked or closed to the government and private vehicles on the day before (the poll), the statement said in a reiteration of the Taliban's first round threat.
Karzai is widely expected to win the second round largely due to his strong support base among fellow Pashtuns -- Afghanistan's largest ethnic group. He remains popular with many Afghans who see him as an experienced leader.

Abdullah is half Tajik and half Pashtun but his main support comes from the mainly Tajik northern provinces.

Both men attracted tens of thousands of supporters during campaigning for the first round. Karzai has promised that he will have an inclusive government if he wins the second round, although he did not give details on how he might to that.

If (Abdullah) wants to come and work in my government, he is most welcome, he told CNN in an interview to be broadcast on Sunday.

Washington is watching the election closely because it forms a key element of Western efforts to stabilize Afghanistan, where it has about 70,000 troops struggling to turn the tide of the growing insurgency.

Obama is considering a call by U.S. General Stanley McChrystal, commander of U.S. and NATO troops in Afghanistan, for tens of thousands more soldiers. Obama said this week he could reach a decision on extra troops before the November 7 vote.

(Additional reporting by Hamid Shalizi; Editing by Paul Tait)

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