By Qasim Nauman
ISLAMABAD (Reuters) - Pakistan's army chief has said a memo accusing the military of plotting a coup, which could damage the unpopular president and led to the resignation of Islamabad's ambassador to Washington, was an attempt to hurt national security, newspapers said.
General Ashfaq Kayani, arguably the most powerful man in Pakistan, made the remarks in a statement filed to the Supreme Court, which is examining a petition demanding an investigation into who was behind the memo.
The petition was filed by President Asif Ali Zardari's main political opponent, Nawaz Sharif. Hearings on the petition are due to start in the Supreme Court on December 19.
Pakistan's envoy to the United States, Husain Haqqani, denied involvement in the memo but resigned over the controversy, which could undermine the deeply unpopular Zardari if he is implicated.
Local newspapers quoted Kayani as saying the memo "has an impact on national security" and "unsuccessfully attempts to lower the morale of the Pakistan army."
Businessman Mansoor Ijaz, writing in a column in the Financial Times on October 10, said a senior Pakistani diplomat had asked that a memo be delivered to the Pentagon with a plea for U.S. help to stave off a military coup in the days after the raid that killed al Qaeda leader Osama bin Laden in May.
Ijaz later identified the diplomat as Haqqani.
No evidence has emerged that the military was plotting a coup and the Pentagon at the time dismissed the memo as not credible.
Zardari is in Dubai for medical treatment that raised speculation he would resign. He is due to return to Pakistan, where he will face one of the biggest challenges of his career.
Tensions between Pakistan's civilian government and military have bedeviled the nuclear-armed South Asian country for almost its entire existence, with the military ruling the country for more than half of its 64-year history after a series of coups.
Haqqani's resignation was seen by many analysts as further weakening the civilian government, which is already beset by allegations of corruption and incompetence.
A new showdown would bring fresh turmoil to one of the most unstable countries in the world and distract Pakistani leaders from addressing a range of issues -- from a Taliban insurgency to power cuts and a struggling economy.
The army seems to want investigators to move quickly to get to the bottom of what has been dubbed "memogate."
"I also recommended to the prime minister that time was of the essence and that the earlier we knew the truth the better it would be to address the negative fallout for the country," The News quoted Kayani as saying.
Pakistan is also facing turbulence on the diplomatic front. Relations with strategic ally the United States, a source of billions of dollars in aid, are at a low point.
The latest crisis in ties erupted after a November 26 NATO cross-border air attack killed 24 Pakistani soldiers.
(Writing by Michael Georgy; Editing by Paul Tait)