Pentagon spokesman Lt Col Koné Faulkner said the United States military would aim to spend the money on other "urgent priorities".
Some analysts warn there may be no real way to pressure Islamabad and say a suspension in aid could see the U.S. lose crucial influence over Pakistan which will instead look to other countries for support, particularly its longtime ally China.
Qureshi said that now Pak-US ties are suspended, adding that US Secretary of State will be visiting Pakistan soon.
The US State Department has previously criticised Pakistan, a key ally, for failing to deal with terrorist networks operating on its soil, including the Haqqani network and the Afghan Taliban.
Pakistan has denied the Trump administration's charges that it is harboring militants involved in a 17-year war in neighboring Afghanistan.
Though the funds have been withheld this year, Pakistan could again be eligible next year for CSF, with USA officials saying that Islamabad could win back that support if it changed its behaviour.More news: Trump warns Canada 'will be out' of trade deal unless it's 'fair'
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In a new blow to deteriorating ties, US Defense Secretary Jim Mattis, who had an opportunity to authorise the said $300 million in CSF funds through this summer - if he saw concrete Pakistani actions to go after insurgents - chose not to do so, despite some US officials having held out the possibility that Islamabad could win back that support if it changed its behaviour.
The Pentagon's remarks come ahead of a planned visit on September 5 to Islamabad by Pompeo, who will be accompanied by the top USA military officer, General Joseph Dunford. He said another $500 million in CSF was stripped by Congress from Pakistan earlier this year, to bring the total withheld to $800 million.
In March, a senior US official said Islamabad had "done the bare minimum to appear responsive to our requests". Combating militants is to be a "primary part of the discussions" in Pakistan, defence secretary James Mattis told reporters last week. The US and others have long complained that Pakistan provides safe haven to militant networks, allowing them to carry out cross-border attacks in Afghanistan. Pakistan is also likely to approach the International Monetary Fund (IMF) for a bailout package soon.
Reuters reported in August that the Trump administration has quietly started cutting scores of Pakistani officers from coveted training and educational programs that have been a hallmark of bilateral military relations for more than a decade.
This isn't the first time the Pentagon has canceled these kinds of funds but this year, as Pakistan's economy struggles, the move may get more attention from Imran Khan, the new leader.
Pakistan could again be eligible next year for CSF.