The United States has called on Pakistan to punish those behind a deadly suicide attack on Indian troops in disputed Kashmir amid escalating tensions between Islamabad and New Delhi.

The February 14 attack in the Himalayan region, which killed more than 40 Indian soldiers, was claimed by the Pakistan-based Jaish-e Mohammed (JeM) militant group.

India has warned Pakistan of a "jaw-breaking response" to the suicide attack, the deadliest incident in the region for decades.

"We have been in close communication with the government of India to express not only our condolences but our strong support for India as it confronts this terrorism," U.S. State Department spokesman Robert Palladino told reporters on February 19. "We urge Pakistan to fully cooperate with the investigation into the attack and to punish anyone responsible."

India called on Pakistan to take "credible and visible action" against the perpetrators of the attack, rejecting Prime Minister Imran Khan's offer to investigate any evidence offered by New Delhi.

India has long accused Pakistan of supporting militants in Muslim-majority Kashmir, which is divided between the two nuclear archrivals but claimed in full by both since independence from British colonial rule in 1947. The two neighbors have fought two of their three wars over the Himalayan territory.

Islamabad has recalled its ambassador from New Delhi for consultations and Pakistan's foreign minister wrote a letter to the United Nations, asking it to help de-escalate tensions with India.

The minister, Shah Mahmood Qureshi, informed UN Secretary-General Antonio Guterres in his letter that "for domestic political reasons, India has deliberately ratcheted up its hostile rhetoric against Pakistan and created a tense environment," the Foreign Ministry said on February 19.

"We are deeply concerned at the increasing tensions between the two countries," said UN spokesman Stephane Dujarric on February 19.

Guterres stressed that it was important for "both sides to exercise maximum restraint and take immediate steps" to de-escalate, while also offering to mediate "should both sides ask," said Dujarric.

Meanwhile, India's army said three JeM militants were shot dead on February 18.

Two of the militants were Pakistanis, including the group's "chief operations commander" in Kashmir, Lieutenant General Kanwal Jeet Singh Dhillon said on February 19.

The attack had been "masterminded" by Pakistan, and specifically its main Inter-Services Intelligence (ISI) spy agency, Dhillon also said.

With reporting by AFP, Reuters, AP, dpa, and India Today