Islamabad: A Pakistani parliamentary committee, investigating the memo allegedly sent to US authorities saying that Zardari feared a coup after Osama bin Laden's May 2 killing, will summon the chief of the ISI spy agency and the former envoy to the US for their statements.

Former Pakistani ambassador to Washington Husain Haqqani quit in November over the secret memo.

Pakistani-American businessman Mansoor Ijaz, who has also been summoned, alleged that a 'senior Pakistani diplomat' asked for help in getting a message from Zardari to the then chairman of the US Joint Chiefs of Staff, Admiral Mike Mullen.

Zardari added fuel to fire when he abruptly left the country for medical treatment in Dubai, giving rise to speculation that he feared a coup.

The 17-member Parliamentary Committee on National Security tasked to investigate the matter decided Friday to summon Inter-Services Intelligence (ISI) director-general Lt. Gen. Ahmed Shuja Pasha, Husain Haqqani and Mansoor Ijaz, Dawn News reported.

The committee has already held a couple of meetings and has been briefed by officials from the defence and foreign ministries.

Committee chairman senator Raza Rabbani said: “Everybody required in the probe will be called individually.”