Pakistani and Indian forces exchanged fire across their border at the weekend, a Pakistani spokesman said on Monday, the latest in a series of incidents raising tension between the nuclear-armed rivals.
Relations between the South Asian neighbours have been strained since India suspended a peace process with Pakistan after an assault on the Indian city of Mumbai by Pakistan-based militants in November 2008.
But easing tension between the two countries that compete for influence in Afghanistan would help Western efforts there, US envoy to Afghanistan and Pakistan Richard Holbrooke said on Sunday before flying to India.
In the latest incident, Indian forces using automatic weapons opened "unprovoked firing" on Pakistani positions in the Sialkot area, north of the city Lahore, on Sunday night, a Pakistani paramilitary force spokesman said.
"Our soldiers strongly retaliated and forced them to stop firing," Rangers spokesman Nadeem Raza said.
"We have decided to forcefully respond if they resort to firing again."
Last week, Indian officials said one of their soldiers was killed in firing across the Line of Control, which separates the two sides in the disputed Kashmir region, to the north of the Sialkot area.
Two days earlier, the two sides traded accusations of firing across their border near Lahore.
The border firing underlines the fragility of ties of between the countries which have fought three wars since 1947.
India has long accused Pakistan of backing militants fighting Indian security forces in the Indian part of the Himalayan region of Kashmir.
Pakistan says it only offers political support to what it calls a freedom struggle by the mostly Muslim people of Kashmir.
Both countries claim Kashmir in full but rule it in part.
Violence in Kashmir has subsided since the two countries agreed to a ceasefire across the dividing line there in 2003 and launched a peace process early the next year.
But Indian police and security experts say violence may spike again as hundreds of Pakistan-based militants may have sneaked into Indian-ruled Kashmir in the past few months.
Analysts say Pakistan has been reluctant to help battle Afghan Taliban factions based on its side of the Afghan border, in part because it sees them as potential allies in its 60 years of hostility with India.
Pakistan last week expressed concern over what it called a massive buildup of arms by India and warned that it could jeopardise a regional balance.
Holbrooke told Reuters in an interview in Kabul on Sunday Washington would welcome better relations between Islamabad and New Delhi, but he had no plans to act as a mediator between them.
India is outside Holbrooke's remit as envoy to Pakistan and Afghanistan, and India bristles at the suggestion that Washington is seeking to push them toward a rapprochement with Islamabad as part of an Afghanistan strategy.