Pakistan's information minister offered to resign Sunday, as tensions continued between the civilian government and the country's powerful military over a memo alleging an army plot to seize power in May.

It was not immediately clear if Information Minister Firdos Ashiq Awan was forced to resign or if she quit voluntarily -- a move which could signal growing differences within President Asif Ali Zardari's troubled Pakistan People's Party.

I endorse your leadership (but) I think I am not competent enough to continue as cabinet member and hence submit my resignation, Awan tearfully said at a televised cabinet meeting.

Some analysts say Awan may have been forced to resign due to her failure to convincingly defend the government in the memogate scandal, as it's being called in Pakistan.

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 Pakistan's ambassador to Washington, Husain Haqqani, who denied involvement but resigned over the controversy.

The scandal has reached a fever pitch, and rumours have swirled in recent weeks that Zardari, who left Pakistan for medical treatment in Dubai earlier this month, would be forced out by the military, which has ruled Pakistan for almost half of its 64-year history.

Army chief General Ashfaq Kayani has ruled out the possibility of a coup and the military does not want to be seen as interfering in civilian politics, but there are still several scenarios under which Zardari could be forced out.

The military could use its extensive influence to isolate Zardari, or offer him an honourable exit by guaranteeing he will not face prosecution on long-standing corruption charges.

Kayani has already called for an investigation into who may have been behind the memo which could further undermine the deeply unpopular Zardari.

The Supreme Court is looking into a petition demanding an inquiry into the matter.

(Reporting by Faisal Aziz and Zeeshan Haider; Editing by Chris Allbritton and Yoko Nishikawa)