"We can no longer be silent about Pakistan's safe havens for terrorist organizations," Mr. Trump said.

Unveiling a new strategy for South Asia on Monday that has many elements of continuity from the past, President Donald Trump said the U.S troops would stay in Afghanistan for an open-ended period of time and America would no longer tolerate Pakistan’s policy of harbouring terrorists.

Mr. Trump said America’s strategic partnership with India will deepen in South Asia and the Indo-Pacfic and demanded that India make more financial contribution for the stabilisation of Afghanistan. The President linked this demand to India’s trade surplus with America saying, India makes “billions and billions of dollars” in trade.

In agreeing to continue with American engagement in Afghanistan, Mr. Trump deferred to the advise of conventional military planners in his administration. “My original instinct was to pull out, and historically I like following my instincts,” the President said, adding that once he studied the Afghanistan situation, he changed his mind. He did not announce any increase in troops, but said the military will have more operational autonomy to pursue terrorists, and commanders have been given authority to attack whenever they chose to. “…we will also expand authority for American armed forces to target the terrorist and criminal networks that sow violence and chaos throughout Afghanistan. These killers need to know they have nowhere to hide – that no place is beyond the reach of American arms,” the President said, indicating willingness for a new wave of American offensive against Islamist groups in South Asia.

Also Read Full texts of Donald Trump's speech on South Asia policy

David Petraeus, a former U.S commander in Afghanistan likened the situation to the U.S military presence in South Korea which started in the 1950s and continues till date. Talking to the National Public Radio, the general said the U.S will have to treat Afghanistan on similar lines.

Mr. Trump sought to differentiate his policy from those of his predecessors - he is the third U.S President to oversee the country’s longest war which has entered its 16th year - by saying American involvement in Afghanistan is not for nation building but is limited to “killing terrorists.” He called this policy “Principled Realism.” He blamed his predecessor Barack Obama, without naming him, for the mess in Afghanistan and Iraq, and said the policy “will change dramatically.” “A core pillar of our new strategy is a shift from a time-based approach to one based on conditions. I’ve said many times how counterproductive it is for the United States to announce in advance the dates we intend to begin, or end, military operations. We will not talk about numbers of troops or our plans for further military activities,” he said. He said American would open to a negotiated political settlement with Taliban, if the situation moves in that direction.

However, what he described as “three fundamental conclusions about America’s core interests in Afghanistan” echo his predecessors George W Bush and Mr. Obama. “First: Our nation must seek an honorable and enduring outcome worthy of the tremendous sacrifices that have been made…Second: The consequences of a rapid exit are both predictable and unacceptable… A hasty withdrawal would create a vacuum that terrorists – including ISIS and Al Qaeda – would instantly fill, just as happened before September Eleventh…Third and finally, I concluded that the security threats we face in Afghanistan and the broader region are immense.”

Coming down heavily on Pakistan, Mr. Trump said twenty U.S. designated foreign terrorist organizations were active in Afghanistan and Pakistan: “the highest concentration in any region of the world. For its part, Pakistan often gives safe haven to agents of chaos, violence and terror,” Mr. Trump said, adding that the current practice of Pakistan receiving American aid and giving shelter to terrorists that target American soldiers cannot go on any longer. “We can no longer be silent about Pakistan’s safe havens for terrorist organizations, the Taliban, and other groups that pose a threat to the region and beyond. Pakistan has much to gain from partnering with our effort in Afghanistan. It has much to lose by continuing to harbor terrorists,” he said. The Obama administration had issued similar warnings to Pakistan, and how Mr. Trump could get Pakistan to fall in line remains an open question.

“The threat is worse because Pakistan and India are two nuclear-armed states whose tense relations threaten to spiral into conflict,” the President said. “…and we must prevent nuclear weapons and materials from coming into the hands of terrorists and being used against us,” he said. In both these positions, Mr. Trump signaled continuity with the previous Obama administration.

Secretary of State Rex Tillerson explained the new U.S policy as an effort to force the Taliban to negotiation. “Our new strategy breaks from previous approaches that set artificial calendar-based deadlines. We are making clear to the Taliban that they will not win on the battlefield. The Taliban has a path to peace and political legitimacy through a negotiated political settlement to end the war,” he said in a statement after the President’s speech.

America is looking at the possibility of a military presence inAfghanistan that is similar to what it has in South Korea - more than six decades now - said David Petraeus, a former U.S commander inAfghanistan. Talking to the National Public Radio, before Mr. Trump’s address, the general said the U.S must have a “sustainable, sustained commitment,” in Afghanistan.