Pakistan has rejected India's demand that it cancel a meeting with separatist leaders from the disputed Kashmir region, ahead of crucial talks between the arch-rivals' top security officers in New Delhi on Sunday.
The latest round of recriminations between the two nuclear-armed neighbours leaves the talks, set at a meeting between prime ministers Narendra Modi and Nawaz Sharif in Russia last month, on a knife edge.
While neither side went as far as calling off the talks, each blamed the other for putting them at risk, undermining prospects for substantive debate at a time of rising frontier tension.
Pakistan has insisted on holding talks with the separatist leaders, a step New Delhi on Friday said would be unacceptable. Responding, Pakistan said it would not adhere to India's "advice".
In a statement, Pakistan's foreign ministry said, "Pakistan remains willing to attend the (national security advisers') meeting without any pre-conditions."
India called off peace talks with Pakistan a year ago after its neighbour consulted the separatists ahead of a meeting between their foreign secretaries.
"We wanted to hold talks to build trust but Islamabad has rejected our request. They have soured the mood," said a senior foreign ministry official in New Delhi.
Vikas Swarup, spokesman for India's foreign ministry, said Pakistan's offer to meet with the separatists "would not be appropriate" or in "keeping with the spirit" of a pledge to jointly combat the threat from militants.
Majority-Hindu India and Muslim Pakistan have fought three wars since becoming separate nations in 1947, two of them over the Himalayan region of Kashmir, which both claim in full but rule in part.India has for years accused Muslim Pakistan of backing separatist Muslim rebels in India's part of Kashmir. Pakistan denies the allegations.
India's earlier grudging toleration of meetings between Pakistan and Kashmiri separatists ended after Modi's election last year.