FACTBOX - Key political risks to watch in Pakistan

A young man, injured from the site of a bomb attack, is rushed to treatment at the Lady Reading hospital in Peshawar January 30, 2012.

ISLAMABAD (Reuters) - Pakistan's Supreme Court is set to charge Pakistan's Prime Minister Yusuf Raza Gilani with contempt for his failure to re-open corruption cases against President Asif Ali Zardari. Gilani is due in court on February 13, and is expected to appeal. If convicted he is likely to face jail, and could lose office.

To lose its prime minister would be deeply embarrassing for Pakistan's government, but is not likely to spark a collapse, or threaten the position of the president, who heads the ruling party and has immunity from prosecution as head of state.

Zardari at least seems to have weathered the storm of 'memogate', a scandal over an unsigned memo to the Pentagon that sought U.S. help in reining in Pakistan's generals, who have ruled the nation for more than half of its history.

The memo scandal prompted speculation that the military wants Zardari to quit, but he has said has said he would not leave office. Military officials told Reuters in December that they would like to see Zardari removed, but only through constitutional means.

This uncertainty comes as relations between the United States and its ally Pakistan are at their lowest in years. A NATO cross-border air attack killed 24 Pakistani soldiers in November, and in mid-December U.S. lawmakers agreed to freeze $700 million in aid to Pakistan until it gives assurances it is helping fight the spread of homemade bombs in the region.

Pakistan has closed its borders to trucks carrying supplies to NATO forces in Afghanistan, and late last year it pulled out of an international conference in Germany on the future of Afghanistan, depriving the talks of a key player with historical ties to Taliban militants.

The U.S. has been pressuring Pakistan to go after militant groups on its soil, which take advantage of the porous border with Afghanistan to attack NATO and Afghan troops there. Pakistan's cooperation is considered critical to U.S.-led efforts to stabilise Afghanistan as NATO combat troops prepare to leave the country by the end of 2014.

RATINGS (Unchanged from January unless stated):

MOODY's: B3

S&P: B-

Here is a summary of key risks to watch in Pakistan:

POLITICAL VIOLENCE, GOVERNMENT WEAKNESS

Army chief General Ashfaq Kayani, who has vowed to keep the military out of Pakistan's stormy politics, has dismissed rumours of a military coup, and said the army supported democracy. Still, military sources have told Reuters the army is fed up with Zardari and wants him out of office, but through legal means.

Although his position is largely ceremonial, Zardari wields considerable influence as leader of the ruling party and any forced departure would be a humiliation for the civilian leadership and could throw the country into turmoil.

Political leaders, many of whom are seen as incompetent and corrupt, have offered little guidance. Zardari's government is weak, prone to splits, has limited control over the military and has failed to tackle corruption or reform the economy. Serious problems formulating and implementing policy will continue to deter investment.

The government also faces growing political opposition.

Politician and former cricket star Imran Khan is riding a wave of dissatisfaction with the government, and brought at least 100,000 people onto the streets of Karachi at a December rally which increased the pressure on the civilian government and cemented Khan's standing as a political force.

What to watch:

-- Attacks on politicians, and alliances forming between Islamist parties to challenge the government.

-- Any move by the military to more openly influence political developments.

-- Outcome of the Supreme Court hearing.

WORSENING RELATIONS WITH AMERICA

An American probe into the November border incident found that both U.S. and Pakistani forces were at fault, putting further strain on already deeply damaged ties.

Washington has long pushed for action, military or otherwise, against the Haqqani militant network, one of NATO's deadliest foes in Afghanistan and thought to largely operate from North Waziristan.

Islamabad has repeatedly said its forces were overstretched and it cannot afford to provoke a general tribal uprising.

Reflecting American frustration with Pakistan, and suspicion that there are links between Pakistan's powerful spy agency and militants operating in Pakistan and Afghanistan, there have been many proposals to make U.S. aid conditional on more cooperation in fighting militants such as the Haqqani network Washington believes operates out of Pakistan and battles U.S. troops in Afghanistan.

In February, a leaked NATO report suggested that, according to Taliban detainees questioned, the influence of Pakistan's spy agency over the Taliban was undiminished.

What to watch:

-- A further attack or unilateral raid on Pakistan from NATO forces in Afghanistan. Another attack could conceivably break the alliance completely, putting the war effort in Afghanistan at risk.

-- More aid cuts. December's move could presage greater cuts as calls grow in the United States to penalise Islamabad for failing to act against militant groups and, at worst, helping them.

-- Any further accusations from Washington, how Islamabad responds, and the tone of the rhetoric from both sides. The United States wants Pakistan to bring the Haqqani network into peace negotiations, but is wary of exerting too much pressure on Pakistan and forcing a break in ties.

INTERNAL SECURITY

There has been a noticeable decrease in bomb attacks in Pakistan, but random violence continues to affect parts of the southern port city of Karachi, Pakistan's key financial hub.

More than 1,600 people have been killed in the city in 2011, over half of them in political and sectarian violence, and Pakistan's paramilitary forces have been deployed in the southern port city to try to stabilise violent districts.

The violence and instability are a huge deterrent to foreign investment. Investors are particularly sensitive to attacks in Karachi, home to key financial markets and the central bank.

The deputy commander of the Pakistan Taliban, which has been waging a four-year war against the government in Islamabad, said in December the group was in peace talks with the government, a move that could further fray the U.S.-Pakistan relationship, but Pakistan's government denied the claim, saying it would enter talks only if the Pakistan Taliban disarm and surrender. What to watch:

-- Further attacks by militants. The assaults on high-profile military facilities have shown the continued ability of Taliban fighters to attack even protected targets.

-- Whether talks with the Taliban materialise officially.

EXTERNAL SECURITY

Relations between Afghanistan and Pakistan are strained, with cross-border attacks reported by both sides.

Tension between the neighbours has been heightened by whispering from some Afghan lawmakers that Pakistan's spy agency, the Inter-services Intelligence (ISI), was behind recent assassinations in Afghanistan, something Pakistan vehemently denied.

Pakistan is a critical regional stakeholder, and backing out of the Bonn conference last November sends the message that it wants to pursue its own interests in Afghanistan, possibly at the expense of the West.

Relations with Afghanistan look increasingly fragile after a series of attacks in Afghanistan that Afghan President Hamid Karzai has suggested were tied to Pakistan.

Karzai said Pakistan-based militant group Lashkar-e-Jhangvi claimed responsibility for the bomb attacks in Afghanistan on December 6 that killed 80 Shi'ite worshippers.

He has also said the assassination of former Afghan president Burhanuddin Rabbani, who was charged with leading peace talks with the Taliban insurgency, was planned in Pakistan.

Relations with India have also been shaken by the killing of bin Laden, with some Indian commentators questioning Pakistan's ability and will to contain militant activity. What to watch:

-- Power struggles within the Taliban. Al Qaeda, the Afghan Taliban and Pakistani militants have held a series of meetings aimed at containing what could soon be open warfare between the two most powerful Pakistani Taliban leaders, militant sources said in early January.

-- Drone attacks. Any drone attack that results in high civilian deaths could further damage the U.S.-Pakistan relationship.

-- Attacks in India. An attack with Pakistani fingerprints could spark serious confrontation.

(Editing by Daniel Magnowski)