SCENARIOS - Assessing risks of India, Pakistan confrontation

ISLAMABAD/NEW DELHI (Reuters) - Tension between nuclear-armed Pakistan and India has been running high since militants killed 179 people in an assault on Mumbai in late November.

With relations fraught between rivals who have fought three wars, here is a look at some scenarios that could unfold.

WAR

Highly improbable. No one, except the militants, would want it. The Indian government and military have repeatedly said all options are open -- comments the Indian media and many Pakistanis have interpreted to mean that a military response is possible. But the Indian government has also said war is not a solution. Pakistan says it does not want war but is ready to fight if India starts one. A U.S. State Department spokesmtan said on Wednesday both sides had moved some troops, but overall, there had been some cooperation and tension had not escalated to the point of threatening peace and stability.

If conflict were to begin, analysts see the most likely scenario as an Indian strike on what it sees as militant targets in Pakistani Kashmir or in Pakistan's Punjab province. The Pakistani military has vowed to respond to any such strike "within minutes". Tit-for-tat missile strikes would be followed by the rapid mobilisation of troops along the line separating the two sides in disputed Kashmir and along their international border that runs south to the Arabian Sea. Both sides have hundreds of thousands of soldiers and large amounts of a range of military hardware based near their frontier. Their navies would face off in the Arabian Sea and analysts say India would probably try to block Pakistan's main port of Karachi.

The fear is that strikes and counter-strikes would rapidly escalate between two countries armed with nuclear weapons and various ways of delivering them.

Domestic pressure on India to pursue a military option would rise sharply if militants struck in India again and India believed the attackers came from, or got support from, Pakistan.

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