WASHINGTON: The United States will hold up $255 million in military assistance for Pakistan until it cracks down on suspected extremist groups that threaten neighboring Afghanistan, officials said Thursday, in the first concrete step since President Donald Trump vowed to ramp up pressure on Pakistan.

In his new strategy for the 16-year Afghan war, Trump singled out Pakistan for allegedly harboring Taliban leaders and other militants that are battling American troops in Afghanistan.

Trump's tough words about Pakistan infuriated Islamabad and triggered anti-U.S. protests that Pakistani police have had to use tear gas to disperse.

Although the Trump administration had floated the possibility of curtailing aid, hitting Islamabad with sanctions or severing its status as a major non-NATO ally, it had been unclear until Thursday exactly what types of measures the administration would pursue, or how quickly.

Trump's administration had faced a Sept. 30 deadline either to say that it planned to spend the $255 million, or lose it.

Ahead of that deadline, the administration told Congress that it will indeed use the money, but is putting a "pause" on spending it or on assigning any funds to specific sales of military equipment to the Pakistanis.

State Department officials said the funds won't be released until the U.S. sees that Pakistan is more successfully addressing U.S. concerns about alleged safe havens in the country for groups including the Haqqani network.

The officials weren't authorized to comment by name and requested anonymity.

American officials wouldn't describe any specific steps they were demanding that Pakistan take, nor would they say whether they'd even communicated such steps privately to the Pakistanis.

The vague nature of the U.S. demands on Pakistan, coupled with the split-the-difference approach of putting the promised funds aside indefinitely, suggested the Trump administration was still struggling to settle on its Pakistan policy even after the president unveiled it with fanfare in a prime-time address.

On Afghanistan, too, the plan is a work in progress, with Pentagon officials still determining a final number for how many more U.S. troops will be sent to Afghanistan.

Islamabad has already reacted angrily to Trump's allegation that the country harbors extremists, with the country's lower house of parliament passing a resolution this week denouncing his claim. Security analyst have also warned that isolating Pakistan could lead it to seek closer ties with Russia, Iran and China .— AP