Survivors of the devastating Taliban suicide attack on a restaurant in Kabul told Saturday of the carnage and bloodshed, as details emerged of 21 people, including 13 foreigners, who died in the assault.

Desperate customers hid under tables when one attacker detonated his suicide vest at the fortified entrance to the Taverna du Liban and two other militants stormed inside and opened fire.

Afghanistan's National Security Council, which is chaired by President Hamid Karzai, on Sunday accused "foreign intelligence services" of being behind the deadly attack, in an apparent reference to Pakistan.

Among the dead were three Americans, two British citizens, two Canadians, the IMF head of mission, and the restaurant's Lebanese owner, who was killed as he tried to fire back at the attackers.

A female Danish member of the European police mission in Afghanistan and a Russian UN political officer also died in the Friday evening massacre, which was the deadliest attack on foreign civilians since the Taliban were ousted in 2001.

UN leader Ban Ki-moon paid tribute to the four UN staff killed in the attack - a US citizen of Somali origin, a Pakistani, a Lebanese and a Russian - vowing the UN would maintain its work in Afghanistan despite the attack.

"We heard a big bang and everywhere was dark," Atiqullah, 27, an assistant chef, told AFP by telephone as he attended a funeral for three of the restaurant's guards. "We used a back door to go to the second floor. Our manager went downstairs. We heard some gunshots and later found out that he had been shot dead."

"There was blood everywhere, on tables, on chairs. Apparently, the attackers had shot people from a very close range."

Interior Minister Omer Daudzai said three police officers responsible for security in the upmarket Wazir Akbar Khan district had been suspended pending an investigation.

Among the dead were a Briton and Malaysian working as consultants to the Afghan finance ministry.

AFP