A Taliban suicide squad armed with rockets on Wednesday targeted an Afghan peace conference hosted by President Hamid Karzai that is seeking consensus on how to end nearly nine years of war.

As Karzai addressed 1,600 delegates and Western diplomats at the "peace jirga," rockets exploded and gunfire erupted near the huge air-conditioned tent in Kabul where the conference was taking place.

Officials said suicide bombers wearing explosive-packed vests and dressed in women's burqas had targeted the event, which was being protected by 12,000 security personnel, but that the attack was unsuccessful.

"The area is under our control now and is cleared," interior ministry spokesman Zemarai Bashary told AFP. "Two attackers aged between 17 and 20 years had managed to come to the area using burqas and had entered a house under construction.

"One of them was killed on the first floor and the second on the third floor," he said, declining to identify the security forces involved.

A third potential suicide attacker was taken into custody.

At least five explosions, believed to be caused by rockets, interrupted the opening of the three-day jirga that Karzai hopes will achieve a consensus within the disparate country on how to end nearly nine years of war with the Taliban.

The militia -- which is opposed to peace talks until all foreign troops have left Afghanistan -- claimed it had dispatched four suicide bombers, who were armed with guns and rockets and threatening the jirga from a nearby rooftop.

Karzai left the event on schedule after his address, travelling in his customary armoured convoy, and the meeting continued.

The president appealed to delegates to advise him on how to bring the poverty-stricken country, blighted by three decades of war, out of the current conflict and encourage the Taliban to disarm.

"The Afghan nation is looking at you. They await your decisions, your advice so that you can show the Afghan nation the way to reach peace, to rescue Afghanistan from this suffering and pain," Karzai said.

The UN special representative to Afghanistan, Staffan de Mistura, who was among about 200 diplomats invited to the jirga, predicted a tough road ahead for negotiations on ending the war.

"This is going to be a tough period, a difficult period, every difficult negotiation starts with an attempt of strength by either side," he told reporters.

Critics have warned that the jirga is likely to have only a limited outcome, not least because the Taliban are not officially attending.

It is already the third such conference to bring together Afghanistan's complex mix of ethnic, tribal, religious, geographical and gender interests since the US-led invasion brought down the Taliban's 1996-2001 regime.

Karzai's Western allies, led by the United States, have described the jirga as a milestone in Afghanistan's political maturity.

The number of US and NATO troops, now at 130,000, is set to peak at 150,000 by August as part of a strategy designed to reverse Taliban momentum and boost government authority in the southern provinces of Kandahar and Helmand.

President Barack Obama has said he wants to start drawing down troops from mid-2011.

The jirga elected as its chairman a warlord and former president, Burhanuddin Rabbani, who in a rambling speech conceded that three days might not be enough to "find a solution for all our problems".

"But it is a good beginning and this trend must continue," he said.

The Taliban have dismissed the conference as a propaganda stunt. A spokesman, Zabihullah Mujahid, told AFP by telephone from an undisclosed location that the militia was responsibile for Wednesday's attacks.

The jirga comes after Al-Qaeda announced the death of its number three leader and Afghanistan operations chief, Mustafa Abu al-Yazid, believed to have been killed in a US drone strike in Pakistan late last month.

The jirga is expected to end on Friday with a declaration on what steps should be taken to end the insurgency, what groups should be included in the process and how they should be approached.