"I want to dispel the impression that the military leadership acted unconstitutionally or violated rules," said Prime Minister Yousuf Raza Gilani, according to state television.

His comments, appeared to be a bid to defuse the worst tensions between the country's civilian leaders and the powerful military since a 1999 army-led coup and came a day after a high-level meeting with the military to discuss a possible trilateral summit on the future of Afghanistan.

The current situation cannot afford conflict among the institutions, he added.

Gilani criticised the army chief General Ashfaq Kayani and director general of the military's Inter-Services Intelligence agency Lieutenant-General Ahmed Shuja Pasha earlier this month for filing responses in a Supreme Court investigation into the origins of mysterious memo that has pitted the military against the civilian government.

In an interview with Chinese media, Gilani said the filings were unconstitutional, infuriating the military's high command which responded with a stern press release, warning of very serious ramifications with potentially grievous consequences for the country.

Despite being officially under civilian control, the military sets foreign and security policies. It attracted rare public criticism after U.S. special forces killed al Qaeda leader Osama bin Laden on Pakistani soil in a raid in May 2011, an act seen by many Pakistanis as a violation of sovereignty.

The latest crisis has raised fears of further instability in the nuclear-armed nation fighting a Taliban insurgency.

The United States wants smooth ties between civilian and military leaders so that nuclear-armed Pakistan can help efforts to stabilise neighbouring Afghanistan, a top priority for President Barack Obama.