India-Pakistan tensions may pull in U.S.

Analysts in both countries say the long enmity has one positive aspect -- the two rivals know exactly how far to push each other without crossing the line.

"We may see the composite dialogue process being canceled and steps like that but I don't think there will be hostilities," said Nayar.

C. Raja Mohan, a Singapore-based security analyst, said the mounting row also exposed a rift inside Pakistan.

"There are clear differences within Pakistan toward India policy," he said.

"The struggle that is going on within Pakistan is by civilian leaders to establish supremacy over the military establishment. It's clear the struggle is not over and it's not clear Zardari has the strength to win in that struggle."

He added: "This is not merely about managing a crisis between India and Pakistan. The forces that are threatening the West, the forces that are threatening the civilian democracy in Pakistan and the forces who are acting against India are all interlinked to each other."

(Additional reporting by Zeeshan Haider in Islamabad and Surojit Gupta in New Delhi; Editing by Simon Denyer and Jerry Norton)