Q&A: Renewed instability in Pakistan
A deepening political row between the Pakistani government and its army and judiciary has led to renewed concerns over the stability of the country, which has a history of military coups. At stake is the survival of President Asif Ali Zardari's democratically elected - though weak and unpopular- government.
Why have the military and the government fallen out?
The Pakistan People's Party (PPP) of President Zardari has never enjoyed particularly close relations with the army.
The latest manifestation of this ongoing row reignited spectacularly in October 2011 through what has become known as the "memogate" scandal. This arose in the wake of an anonymous memo unearthed in Washington that sought US help to avert a possible military coup in Pakistan following the killing by US forces of al-Qaeda leader Osama Bin Laden in May.
Pakistan's ambassador to the US at the time, Husain Haqqani, was alleged to have drafted it at the behest of President Zardari, who is alleged to have offered to replace his country's military leadership and sever all ties with militant groups in exchange for US help against the army. The memo was delivered to the then US Joint Chiefs Chairman, Michael Mullen. He admitted receiving it, but insisted that it was not acted upon. The row has already cost Mr Haqqani his job. He denies any role in drafting the memo - as does President Zardari. But the president could be forced to quit if the trail is found to lead to his door.
Why have the judiciary and the government fallen out?
If the PPP's relations with the military have traditionally not been warm, the same can also be said of its relations with the judiciary. The Supreme Court is conducting its own investigation into the "memogate" affair which is separate from a parliamentary inquiry. Petitioners in the case are demanding that Mr Haqqani and President Zardari should be tried on charges of treason.
The judiciary is also pursuing the government over the thorny issue of corruption. In 2009 the Supreme Court overturned an amnesty protecting President Zardari and hundreds of other politicians from being prosecuted for corruption. Pakistan's prime minister now faces contempt charges over the government's refusal to reopen these corruption cases.
Is there likely to be a coup?
Most analysts believe this is highly unlikely, chiefly because there appears to be a rare consensus among Pakistan's political classes that any attempt to stage a military take-over would be universally resisted. There is little that the current army leadership can offer to the rest of the world that would persuade it to support military intervention. Furthermore the military's credibility - both in Pakistan and abroad - is at a historic low following the killing of Osama Bin Laden.
Arguably the most likely scenario is that President Zardari will continue his "play safe" approach and not attempt to replace the leadership of either the ISI intelligence service or the army. But the government is likely to come under increasing pressure from the opposition to call early elections. Its tenure officially comes to an end in February 2013 but it may be pressured into going to the polls well before then. However it will not want to call an election before March, when it hopes to use the provincial legislatures to win a majority in the national senate.
How secure is President Zardari?
After three years in office plagued by misrule and allegations of corruption, no-one is betting at the moment on President Zardari or his government completing their terms of office. The days of a military coup may be gone in Pakistan, many analysts say, but things are about to get a lot tougher for the government.
Perhaps one of the most serious threats to the president comes from the cricketer-turned-politician Imran Khan. The leader of the Tehreek-e-Insaf (Movement for Justice) party is seemingly being propped up as a "third force" to the traditional two major parties, President Zardari's PPP and the Pakistan Muslim League of former PM Nawaz Sharif. Some are genuinely drawn to Mr Khan because he is a political novice with a corruption-free past. Others are flocking to him convinced that he is the military's preferred choice and will therefore offer a dose of urgently needed stability.
Encouraged by the prospect of change and political realignment, former President Pervez Musharraf has also decided to return to the fray - pledging to go back to Pakistan at the earliest opportunity. In the event of early elections, some analysts are predicting an alliance between Mr Khan, Mr Musharraf, the Sindh-based MQM party and a variety of army-backed politicians. Whoever ends up running Pakistan faces a daunting challenge - the economy is in the doldrums, insurgents are active in many parts of the country and relations with the US are the worst in a decade.
How secure is Prime Minister Gilani?
Mr Gilani - like President Zardari - is at the heart of Pakistan's "battle of the institutions". He has been strongly criticised by the army and the judiciary.
In January the military publicly rebuked him, warning of "serious ramifications with potentially grievous consequences" after he criticised military leaders in a media interview. Around the same time the Supreme Court warned that the prime minister could be disqualified from office for not reopening corruption cases against top politicians - a panel of judges even went so far as to accuse him of violating his oaths and not being an honest man. It has more recently issued contempt orders against Mr Gilani, raising the prospect of his prosecution.
Are there any grounds for optimism?
It depends. The BBC's M Ilyas Khan in Islamabad says that Pakistan appears to be heading into a period of massive confusion which many believe could translate either into a stronger parliamentary democracy or a total collapse of the system.
Successive military regimes - or governments controlled by the military - have promoted a militarised society where overall conditions are akin to a "war economy". But against this our correspondent points out that the present democratic administration has survived longer than any other in Pakistani history - which probably explains why the confrontation between the institutions has assumed such alarming proportions.