ISLAMABAD/NEW DELHI: Pakistan began moving thousands of troops to the Indian border yesterday and canceled soldiers’ leave, while India warned its citizens it was unsafe to travel to Pakistan and the prime minister met his military chiefs.

The moves by the nuclear-armed neighbors sharply raised tensions triggered by last month’s Mumbai terror attacks. India has blamed Pakistan-based militants for the siege of its financial capital, which killed 179 people and has provoked an increasingly bitter war of words between the two countries.

The Pakistani troops headed to the Indian border were being diverted away from tribal areas near Afghanistan, officials said, and the move was expected to frustrate the United States, which has been pushing Islamabad to step up its fight against Al-Qaeda and Taleban militants near the Afghan border.

Two intelligence officials said the army’s 14th Division was being redeployed to the towns of Kasur and Sialkot, close to the Indian border. They said some 20,000 troops were on the move.

Earlier yesterday, a security official said all troop leave had been canceled. The officials spoke on condition of anonymity because of the sensitivity of the situation.

“We do not want to create any war hysteria but we have to take minimum security measures to ward off any threat,” a Defense Ministry official said on condition of anonymity.

Both countries have said they want to avoid military conflict over the attacks. But India has not ruled out the use of force as it presses its neighbor to crack down on the Pakistan-based terrorist group it blames for the attacks.

India’s travel warning followed media reports in Pakistan and India that “several” Indian nationals had been held in the last two days after bombings in the Pakistani cities of Lahore and Multan.

“Indian citizens are therefore advised that it would be unsafe for them to travel (to) or be in Pakistan,” India’s Foreign Ministry spokesman said in a statement.

Another Foreign Ministry official said the warning referred to all travel to Pakistan.

Prime Minister Manmohan Singh had earlier discussed tension with Pakistan during a scheduled meeting about military pay with the chiefs of the army, navy and air force, his office said.

“The prime minister met the tri-services chiefs to discuss the pay commission issues but obviously the situation in the region was also discussed,” said an official from Singh’s office, who requested anonymity. There were no other details.

Indian media said national security adviser M.K. Narayanan also attended the meeting.

Late yesterday, India’s high commissioner (ambassador) to Pakistan, Satyabrata Pal, met with the top civil servant in Pakistan’s Foreign Ministry, Salman Bashir, a spokesman said.

“Pakistan-India relations and the current situation came under discussion during the meeting,” the spokesman, Mohammad Sadiq, said.

Pakistani Prime Minister Yousaf Raza Gilani has promised to respond aggressively if attacked, but reassured India yesterday that Pakistan would not strike first. “We will not take any action on our own,” Gilani told reporters. “There will be no aggression from our side.”

Many analysts say it is very unlikely that the tension will descend into war. The uneasy neighbors have fought three wars since independence in 1947 and came to the brink of a fourth in 2002 after an attack on the Indian Parliament.

“We hope that both sides will avoid taking steps that will unnecessarily raise tensions during these already tense times,” US National Security Council spokesman Gordon Johndroe told reporters in Washington.

China emerged as a potential peace broker after Foreign Minister Yang Jiechi unexpectedly called his counterparts in New Delhi and Islamabad in the past two days. China has long been a close ally of Pakistan, while India and Washington have been building close ties.

A statement on the Chinese Foreign Ministry’s website said Yang urged both sides to continue dialogue and that China was willing to work with the international community to protect peace and security in South Asia.

A senior government official in New Delhi said Yang had suggested a meeting between Indian and Pakistani officials.