The tough message from the US came after an angry tweet from President Donald Trump on New Year's day that America had been rewarded with "nothing but lies and deceit" by Pakistan in return for its over USD 33 billion aid in the last 15 years.
Soon after the president's tweet, the White House confirmed that the US had suspended its USD 255 million military aid to Pakistan.
US Ambassador to the UN Nikki Haley came out in support of Trump's decision to block aid to Pakistan and said, "There are clear reasons for this. Pakistan has played a double game for years."
The Trump administration expects far more cooperation from Pakistan in the fight against terrorism, she said.
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"Trump is willing to go to great lengths to stop all funding for Pakistan as they continue to harbour and support terrorism," Haley said.
The Indian-American diplomat said the aid issue was connected solely to Pakistan's harbouring of terrorists.
State Department Spokesperson Heather Nauert, speaking at her daily news conference, described Pakistan as an "important partner" and said Islamabad must do more to combat terrorism.
"Pakistan is an important partner. We have a lot of issues in that region. Pakistan knows that, we all know that, and we try to work carefully together on some of those issues. I don't want to say that Pakistan can do more, but Pakistan knows what it needs to do," she said.
Speaking about the US' decision to withhold USD 255 million military aid to Pakistan, Nauert said the decision was taken in August and Pakistan would need to "earn" such assistance through sincere action.
Nauert said Secretary of State Rex Tillerson and Defence Secretary Jim Mattis, who visited Pakistan in the last couple of months, had conveyed the same message to the country's leadership.
The White House also defended Trump and asked Pakistan to do more to combat terrorism.
"We know that Pakistan can do more to fight and stop terrorism and we want them to step up and do that. That seems pretty simple," White House Press Secretary Sarah Sanders told reporters in Washington.
"The president outlined a new strategy for Afghanistan and South Asia earlier this past year, in August. And at that time, he laid out and said that Pakistan is not fulfilling its obligations," said Sanders.
Trump in August announced his new South Asia policy and accused Pakistan of harbouring terrorists.
"The president is simply following through on a commitment that he made, because this is a president who does what he says he's going to do," she said.
Pakistan yesterday expressed "deep disappointment" over Trump's allegations, saying the accusations strike with "great insensitivity" at the "trust" between the two countries.
Pakistan also summoned the US Ambassador David Hale to register its protest after president Trump's tweet.