The Taliban made good on its threats to attack a national peace conference in Afghanistan on Wednesday, as suicide attackers descended on the conference on its opening day.

Reports say three militants breached the massive security cordon around the conference tent in Kabul by disguising themselves with burqas. They reportedly carried explosives and were armed with guns and at least one grenade launcher.

Two attackers were killed in ensuing gunfire and one arrested. None of the 1,600 Afghan delegates were hurt.

The attack started within minutes of President Hamid Karzai beginning his opening address to the peace conference, called a jirga. The conference, scheduled to continue for three more days, resumed shortly afterward.

The Taliban later claimed responsibility for the attack.

The jirga has been planned as a way to offer peace to militants willing to lay down their arms, by offering them jobs, training and financial help.

The Taliban strongly opposes the jirga. It said in a statement before its opening: "Obviously, the jirga will provide yet another pretext for America to continue the war in Afghanistan, rather than bringing about peace in the country."

Karzai appealed to the Taliban in his jirga address, telling them their actions were keeping the international forces that they resent, in the country.

"You should provide the opportunity for the foreign forces to leave," Karzai told the delegates.

"Make peace with me and there will be no need for foreigners here. As long as you are not talking to us, not making peace with us, we will not let the foreigners leave."

After Karzai finished his speech he left in a convoy of armoured vehicles as helicopters hovered overhead.

Karzai has hoped the jirga would bolster him politically, as he fights to restore his popularity after an election last year that was mired in controversy. But the U.S. has been skeptical of peace talks with the Taliban leadership.

Washington has said it supports economic incentives to individual insurgents willing to abandon al Qaeda, but it would prefer first to weaken the militants on the battlefield.

Some expressed skepticism the conference could help bring peace. That's in part because while the delegates include individuals with links to militants, there are no active members of the Taliban and other insurgent groups.

Prominent civil society activist Sima Samar, the head of the Afghan Human Rights Commission, questioned whether anything would be achieved.

"I'm not very hopeful that we will come up with a workable mechanism to go for peace. The reason is we don't have the opposition with us. It's obvious from their attacks," Samar told AP.

Abdul Sattar Khawasi, a lawmaker from Parwan province attending the jirga, said the ability of the militants to launch the attack underscored the weakness of Karzai's administration.

"Unfortunately this shows the weakness of the government, and the weakness of the security forces, that they were unable to provide enough security for this consultative peace jirga," he said.

With reports from the Associated Press