In his South Asia strategy speech last week, President Donald Trump publicly put Pakistan on notice that it must stop providing sanctuaries to armed groups that are fighting in Afghanistan.
"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," said Trump, laying out his "condition-based approach" to defeating terrorism in Afghanistan.
"We have been paying Pakistan billions and billions of dollars at the same time they are housing the very terrorists we are fighting. But that will have to change and that will change immediately," he vowed.
Washington and Kabul have long accused Islamabad of turning a blind eye on the issue of safe havens to Afghan Taliban and the notorious Haqqani network, a U.S.-designated terror organization.
Analysts charge that sanctuaries in Pakistan have helped the militants sustain a bloody insurgency in Afghanistan against the Western-backed Afghan government.
"Top leaders of both groups [Taliban and the Haqqani network] enjoy the ability to live freely in certain parts of Pakistan — mainly Baluchistan province, but also some of Khyber-Pakhtunkhwa," Michel Kugelman, a South Asia analyst at the Woodrow Wilson Center in Washington, told VOA.
"It is not just the leaderships of these groups that enjoy Pakistani largesse; it's the fighters, too," he added.
Where are the sanctuaries?
Afghan Taliban's leadership council, known as the Quetta Shura, is reportedly based in the Pakistani southwestern city of Quetta, which shares a border with Afghanistan's Kandahar province, the traditional stronghold of the Afghan Taliban.
The Haqqani network, one of the most notorious terror groups in the region, is reportedly based in Miram Shah, a town in the Federal Administered Tribal Areas (FATA) of northern Pakistan. The group, which has been blamed for numerous deadly attacks inside Afghanistan against U.S.-led NATO forces and the Afghan government, is reportedly operating with impunity from across the border.
The Afghan government charges that militant sanctuaries are the main reason behind the country's instability.
"Neighbor countries have been a major part of the problem in Afghanistan. Terrorists' safe havens and sanctuaries are out of Afghanistan, where they get support, training and equipment," Ahmad Shah Katawazai, a defense liaison at the Afghan embassy in Washington, told VOA.
Pakistan maintains that the Afghan Taliban controls large swaths of territory inside Afghanistan and does not need to have sanctuaries inside Pakistan.
"They don't need hideouts or sanctuaries in Pakistan. They have vast territory [under their control], which is beyond Kabul's writ, at their disposal. Why would they come to Pakistan for sanctuaries?" Pakistan Foreign Minister Khawaja Asif said over the weekend.
Following Trump's speech, Pakistan denied the allegations that it harbors militants and cited its sacrifices in the ongoing war against terror as an example of how the country itself has been a victim of terrorism.
In an effort to illustrate its displeasure at the U.S president's speech, Pakistan postponed Asif's planned trip to Washington and also delayed a planned visit by U.S. Assistant Secretary of State Alice Wells to Islamabad.
Could the U.S. take unilateral action?
As the administration is weighing its options to deal with the issue of sanctuaries in Pakistan, some analysts doubt Pakistan will take action against militants operating from its soil unless more rigorous pressure is applied on the country.
"The Trump administration will need to deploy new forms of pressure. Previous forms of pressure — threats, aid conditionalities and aid cuts — have not worked. The administration will need to step up its actions and make them much more draconian — and this is clearly already under consideration," Kugelman, of the Woodrow Wilson Center, told VOA.
Meanwhile, David Des Roches, an associate professor at the National Defense University in Washington, believes that while it is unlikely that the Pakistanis would back down publicly, it "is quite possible that they will facilitate enhanced American action against militants in Pakistan."
What seems unclear so far is to what lengths the U.S. is willing to go as far as tackling the issue of safe heavens in Pakistan.
While talking to reporters at the State Department last week, U.S Secretary of State Rex Tillerson hinted that the U.S. would target terrorists "wherever they live" without elaborating further.
"There's been an erosion in trust because we have witnessed terrorist organizations being given safe haven inside of Pakistan to plan and carry out attacks against U.S. servicemen, U.S. officials, disrupting peace efforts inside of Afghanistan," Tillerson said.
Zalmay Khalilzad, a former U.S. ambassador to Afghanistan, Iraq and the United Nations, told VOA that the U.S. should target Taliban and Haqqani network sanctuaries inside Pakistan and push Islamabad "out of its comfort zone."
"Pakistan has become comfortable with its dual policy; receives U.S. assistance and works to defeat the U.S. in Afghanistan," Khalilzad said.
He advocated for sanctions against senior military and intelligence officers who support extremist groups.
"Take Pakistan off the list of major non-NATO ally, which provides the opportunity to receive significant security assistance; suspend assistance program; push IMF, World Bank, and Asian and European allies to suspend assistance programs," Khalilzad added.
"If America imposes sanctions, Pakistan will probably be unable to receive assistance from IMF and the World Bank, and international companies will not be willing to invest in Pakistan," Saad Mohammad Khan, a retired Pakistani military leader, told VOA.
VOA Deewa contributed to this report.