Afghan refugees pack their belongings onto a truck at the United Nations High Commissioner for Refugees repatriation center on the outskirts of Quetta, Pakistan, on Aug. 26, 2015. They are preparing to return to their home country after fleeing civil war and Taliban rule. (Banaras Khan/AFP/Getty Images)

For decades, Afghans fleeing conflict have found a tenuous haven in next-door Pakistan, which has allowed millions to settle there but periodically threatened to send them back. Now, amid new tensions with Washington over drone strikes and fighter jet subsidies, Pakistan says it plans to deport at least 1.5 million refugees within the next two weeks.

According to a report Friday by Bloomberg News, Pakistani military officials say they need to return the refugees as part of a "border management program." But experts say such a move would provoke a humanitarian disaster in Afghanistan, which is ravaged by poverty, economic stagnation and an aggressive Taliban insurgency that has displaced more than 1 million people from their rural homes.

"Afghanistan isn't now prepared to embrace a large influx of Afghan immigrants from neighboring nations, given the security problems and lack of resources," an adviser to the Afghan Ministry of Refugees and Repatriation in Kabul told the news service.

The struggling country has already absorbed several million returnees since 2001, when the extremist Taliban regime fell and an elected government took power with Western backing. Over the past year, moreover, hundreds of thousands of desperate Afghans have fled to Europe, joining the mass flood of illegal migrants from the Middle East.

But there are signs that the threat of forced mass repatriations may be mostly a rhetorical salvo in the complicated political game between Pakistan and the United States over Pakistan's role in the ongoing Afghan conflict. Pakistani civilian officials said this week that they seek a "dignified" return for long-term refugees and may allow them to remain through the end of 2017, as international rights groups have urged.

The immediate cause of Pakistan's umbrage, experts said, is not the burden of harboring a longtime refugee population but official pique over two recent moves by Washington: a recent drone strike that killed Afghan Taliban leader Mullah Akhtar Mansoor inside Pakistan and a refusal by Congress to provide financial subsidies for F-16 fighter jets that the Pakistani military has long sought to buy from the U.S.

Analysts in Pakistan say that U.S. officials see Pakistan as a hindrance to peace negotiations with the Taliban, whose top leaders have often been sheltered there, and are trying to put pressure on its powerful military establishment. In turn, they said, Pakistan is using the refugees as pawns to remind the United States of its essential role in the region as it seeks more foreign military aid and a dominant hand in shaping the peace talks.

"Both sides are playing their cards," one research center director in Islamabad, Mansur Khan Mahsud, told Bloomberg. Pakistan's attitude toward the U.S., he said, is "if you are building pressure, I'll do the same to counter you."

Still, the issue has already created new tensions along the Afghan-Pakistan border, where fighting has broken out several times since Pakistan tightened security after Mansoor's killing and troops tried to erect a new gate at the busy main border crossing.

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