Foreign Minister Khawaja Asif on Thursday called on ex-president Asif Zardari to "rein in" former ambassador to the United States (US), Hussain Haqqani, accusing the latter of "authoring" President Donald Trump's new South Asia policy.

Asif, in a tweet, said: "President Zardari instead of criticising [the] government, [should] rein in Haqqani his ambassador to US, taking credit of authoring US policy President Trump announced."

Haqqani responded to the tweet soon after, saying Pakistan's foreign minister should "deal with the policy instead of trying to bully an exiled Pakistani on Twitter."

Haqqani, who remained Pakistan's ambassador to the US from 2008-2011, was allegedly disowned by the PPP after he authored an article in The Washington Post claiming his ‘connections’ led US to kill Osama bin Laden.

Asif's tweet comes days after the US administration, signalling a shift in their policy towards Pakistan, threatened to cut off aid to Pakistan for providing 'safe haven' to terrorists.

"We can no longer be silent about Pakistan's safe havens for terrorist organisations," Trump had said earlier this week, warning that vital aid could be cut.

"We have been paying Pakistan billions and billions of dollars at the same time they are housing the very terrorists that we are fighting," he said. "That will have to change and that will change immediately."