Pakistan has started to redeploy thousands of troops to the Indian border from the tribal areas near Afghanistan, intelligence officials said Friday, raising tensions triggered by the Mumbai terror attacks. India has blamed Pakistani-based militants for last month's siege on its financial capital, which killed 164 people and has provoked an increasingly bitter war of words between nuclear-armed neighbors that have fought three wars in 60 years. The troops headed to the Indian border were being diverted away from tribal areas near Afghanistan, the two officials said, and the move was expected to frustrate the United States, which has been pushing Pakistan to step up its fight against al-Qaida and Taliban militants near the Afghan border. The officials said elements of the army's 14th Infantry Division were being redeployed to the towns of Kasur and Sialkot, close to the Indian border. The military began the troop movement Thursday and plans to shift a total of 20,000 soldiers, they said without providing a timeframe. Earlier Friday, a security official said all troop leave had been canceled. The officials spoke on condition of anonymity because of the sensitivity of the situation. India and Pakistan 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 Pakistani-based terrorist group it blames for the attack. Pakistani Prime Minister Syed Yousuf Raza Gilani has promised to respond aggressively if attacked but reassured India Friday 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." Meanwhile, Indian Foreign Minister Pranab Mukherjee accused Pakistan of trying to divert attention away from its struggle to rein in homegrown terror groups like Lashkar-e-Taiba, which Delhi accuses of masterminding the Mumbai attacks. "They should concentrate on the real issue: how to fight against terrorists and how to fight against and bring to book the perpetrators of (the) Bombay terrorist attack," he said. Pakistan has arrested several senior members of the banned group and cracked down on a charity the US and UN say was a front for Lashkar. India has demanded greater action, but Pakistan says it needs to share evidence backing up its claims. Mukherjee responded Friday by saying India had provided more than enough evidence about the militants, who infiltrated Mumbai by sea. "We have indicated to them that there are ample evidences from the log book of the captured ship, from the information available from satellite telephones and various others that elements from Pakistan were responsible for this attack," Mukherjee told reporters. Earlier, Indian Prime Minister Manmohan Singh met Friday with the chiefs of the army, navy and air force to discuss "the prevailing security situation," according to an official statement. An Associated Press reporter in Dera Ismail Khan, a district that borders Pakistan's militant-infested South Waziristan tribal area, said he saw around 25 trucks loaded with soldiers and equipment heading away from the Afghan border Friday. A senior security official confirmed that soldiers were being moved out of the border area, but said it was "a limited number from areas where they were not engaged in any operation." He declined further comment and asked his name not be used, citing the sensitivity of the situation. The White House said it was discussing the reported troop movements with US embassies in the region and was urging both countries to cooperate in investigating the attacks and fighting terrorism. "We hope that both sides will avoid taking steps that will unnecessarily raise tensions during these already tense times," said White House spokesman Gordon Johndroe. Analysts said the redeployment was likely meant as a warning to India not to launch missile strikes against militant targets on its territory, a response that some have speculated is possible. "It is a message to India that if you think you can get away with strikes, you are sadly mistaken," said Talat Masood, a retired general and military analyst based in Islamabad. Pakistan and India have fought three wars since their independence from Britain in 1947, two over Kashmir, a Muslim majority region in the Himalayas claimed by both countries. They came close to a fourth after suspected Pakistani militants attacked India's parliament in 2001. Both countries massed hundreds of thousands of troops to the disputed Kashmir region, but tensions cooled after intensive international diplomacy. News of the buildup comes as Indian officials say militant activity in Indian Kashmir has fallen to its lowest levels since an anti-India militant movement began there in 1989. The number of militant attacks fell 40 percent from 2007-2008, reaching 709 this year from roughly 1,100 last year, Kuldeep Khoda, a senior police official, said in a statement. Police say there are 850 militants fighting in the region, including followers of Lashkar-e-Taiba, which is widely believed to be a creation of Pakistani intelligence in the 1980s and used to fight Indian-rule in Kashmir. Indian authorities say the decrease in attacks is the result of an experienced security apparatus that has struck at the heart of many militant groups _ Khoda said Indian forces have killed about 350 militants this year, including some top-ranking commanders. But they also say that the militants have scaled back their attacks as a large public protest movement gained momentum since last summer. Pakistan has deployed more than 100,000 soldiers in Waziristan and other northwestern regions to fight Islamic militants blamed for surging violence against Western troops in Afghanistan as well as suicide attacks in Pakistan. Security officials have previously said the country would be forced to withdraw troops from the Afghan border if tensions with India - whose army is twice as large - escalated. "This is a serious blow to the war on terror in the sense that the whole focus is now shifting toward the eastern border," said Masood. "It will give more leeway to the militants and increased space to operate." The United States wants Pakistan to stay focused on the fight against militants in the border region, where Osama bin Laden and other top al-Qaida leaders are believed to be hiding.