Hamid Karzai, the Afghan president, has said an assassination attempt against Afghanistan's spy chief "came from Pakistan".

Speaking in the Afghan capital on Saturday, Karzai said though the Taliban claimed responsibility for Thursday's attempt on the life of Asadullah Khalid, head of the National Directorate of Security, the attack originated in Quetta.

"Of course we will be seeking clarification from Pakistan because we know this man who came in the name of a guest to meet Asadullah Khalid came from Pakistan. We know that for a fact", he said.

Karzai stopped short of directly implicating his neighbour to the south, but did say he would demand clarification from Islamabad.

He said the attack, in which an explosive was hidden in the underwear of the bomber, was beyond the Taliban's capabilities.

"Apparently the Taliban claimed responsibility like many other attacks," Karzai said.

"But such a complicated attack and a bomb hidden inside his body, this is not Taliban work ... It's a completely professional [job] ... Taliban cannot do that and there are bigger and professional hands involved in it."

Karzai said the issue would be discussed next week with Pakistani officials during a meeting between the foreign

ministers of Afghanistan, Pakistan and Turkey in Ankara.

For its part, Pakistan's foreign ministry said: "before levelling charges, the Afghan government would do well if they shared information or evidence with the government of Pakistan that they might have with regard to the cowardly attack on [Khalid]".

Khalid, who had been appointed the new head of the Central Asian nation's spy agency in September despite allegations of torture and drug trafficking, was in a Kabul guest house when a suicide bomber posing as a peace envoy left him wounded.

Before his role as spy chief, Khalid had served as the minister of tribal and border affairs and the governor of southern Kandahar province for three years starting in 2005.