SPIN BOLDAK, Afghanistan - Thousands of Taliban suicide bombers have been deployed across Afghanistan to attack Western troops and the government, the group's military chief said on Monday.Following last year's violence, the worst since the Taliban's ouster in 2001, this year is regarded as the crunch period both for the Taliban and U.S.-led Western troops.

Speaking to Reuters by satellite phone from an undisclosed location, Mullah Dadullah, the Taliban's military head, said the Islamic guerrillas had the ability and the weapons to fight foreign troops for a long time.

"We have sent thousands of Taliban suicide bombers to all Afghan cities for attacks on foreign troops and their Afghan puppets," Dadullah said.

"And we will turn our motherland into the graveyard of the U.S forces and their families should wait for their dead bodies. The Taliban's war is only for the freedom of Afghanistan from the enemies of Muslims."

Afghan defense ministry spokesman Zahir Azimi dismissed Dadullah's comments as psychological tactics.

"We have two types of war; face-to-face war and psychological war. The Taliban have suicide bombers, but there is no doubt that they are exaggerating the numbers and use it as a psychological tool," he said.

Suicide attacks, copied from militants in Iraq, increased dramatically in 2006. On Sunday, a suicide attack on an Afghan army convoy in the eastern province of Laghman killed nine people, including children and two troops.

After taking serious losses last year confronting NATO forces in conventional pitched battles, the Taliban are returning to traditional guerrilla tactics, especially suicide bombings.

The Taliban and their Islamic allies, including al Qaeda, are mostly active in southern and eastern regions bordering Pakistan.

Close to 4,000 people, nearly a quarter of them civilians, but also including around 170 Western soldiers, hundreds of militants, Afghan troops and dozens of aid workers were killed in fighting last year.

U.S.-led forces overthrew the Taliban's Islamist government after its leadership refused to hand over Osama bin Laden following the September 11 attacks on the United States.

The Afghan government says Taliban's elusive leader, Mullah Mohammad Omar, and his senior aides live in Pakistan, the key Taliban supporter until September 11.

Islamabad concedes rebels cross the border, but denies supporting the Taliban or that rebel leaders are on its territory. Dadullah said Omar and the Taliban leadership were in Afghanistan.

(With additional reporting and writing by Sayed Salahuddin)

© Reuters 2007.