The United States has announced it will suspend security assistance to Pakistan for failing to take "decisive action" against Taliban militants targeting US personnel in neighbouring Afghanistan.
- The aid suspension follows a tweet from Donald Trump saying Pakistan gave "nothing" for US assistance
- Pakistan called the comments "incomprehensible"
- The US State Department says the aid will be suspended until Pakistan takes action against terrorism
The State Department's declaration signalled growing frustration over Pakistan's cooperation in fighting terrorist networks, but it was not immediately clear how much money and materiel was being withheld.
The vague details suggested the primary goal was to substantiate President Donald Trump's surprising New Year's Day tweet that accused Pakistan of playing US leaders for "fools".
Spokeswoman Heather Nauert said the restrictions covered security assistance above and beyond the $US255 million ($325 million) for Pakistani purchases of American military equipment that the administration held up in August.
Ms Nauert said details were still being worked out on the additional funds, and referred questions to the Defence Department.
Earlier, Defence Secretary Jim Mattis said the policy on military aid was "still being formulated".
Ms Nauert made clear the $255 million was still blocked.
The new action targets payments of so-called Coalition Support Funds that the US pays to Pakistan to reimburse it for its counterterrorism operations.
Those funds are typically paid later in the year, and already require US certification, so the effect of the State Department's announcement was unclear.
On the same day, the State Department accused Pakistan of severe violations of religious freedom, adding the country to a special watch list, pursuant to 2016 legislation.
Mr Trump had long argued Pakistan had not done enough to fight the threat of extremism in the region, and this week's tweet reiterated his view that the country gives "safe haven to the terrorists we hunt in Afghanistan".
Mr Trump unveiled in August a South Asia strategy aimed at ending the stalemate in the US war in Afghanistan, now entering its 17th year.
Ms Nauert said that despite sustained high-level engagement with Pakistan's Government, "the Taliban and Haqqani network continue to find sanctuary inside Pakistan as they plot to destabilise Afghanistan and attack US and allied personnel".
She said until Pakistan takes "decisive action" against those groups, security assistance was suspended.
Civilian development and economic assistance to Pakistan is not affected.
Pakistan had earlier called Mr Trump's tweet "completely incomprehensible" and at odds with recent "trust-building" visits by Secretary of State Rex Tillerson and Mr Mattis.
The haphazard nature of the State Department's announcement suggested it had been hastily arranged rather than developed a traditional policy process.
Even after members of Congress had been notified of an impending aid suspension, White House and State Department officials were still hammering out details for who would announce it and when.
US assistance to Pakistan, which rose sharply after the 9/11 attacks, has been declining since 2011 when American commandos killed Osama bin Laden inside Pakistan, straining relations.
Pakistan has increasingly turned for economic support to northern neighbour China, which is investing tens of billions in transportation links and power generation as it extends its strategic footprint across Asia.