Donald Trump reportedly hangs up on Malcolm Turnbull

US President Donald Trump has blasted a refugee deal between Australia and the US on Twitter, calling it a "dumb deal".

It came on the same day reports emerged that Mr Trump hung up on Australian Prime Minister Malcolm Turnbull and bragged about the scale of his electoral college win.

In one of many routine phone calls to leaders of countries on Saturday (local time),
Mr Trump told Mr Turnbull that a previously confirmed agreement where the United States would take 1250 refugees from an Australian detention centre was "the worst deal ever" and accused Australia of seeking to export "the next Boston bombers", Washington Post reports. 

At one point Mr Trump informed Mr Turnbull that out of the four phone calls to other world leaders that day, including Russian President Vladimir Putin, this one was " the worst call by far."

Trump on the phone with Turnbull Getty

He reportedly said "I don't want these people" while discussing the resettlement deal with Mr Turnbull, and vowed to subject each refugee to "extreme vetting". 

Mr Trump tweeted about the deal at around 5pm today (NZ time), vowing to "study this dumb deal!" 

The reports come from senior US officials who were witness to the conversation. But Mr Turnbull refused to comment on the nature of the discussion. At a news conference in Australia he told media that "these conversations are conducted candidly, frankly, privately".

"If you see reports of them, I'm not going to add to them." 

He stressed that the relationship between the two countries is still "very strong". 

Australia and the United States have historically been allied over many issues; supporting each other diplomatically and fighting alongside each other in numerous wars, including the recent Iraq and Afghanistan sieges. 

The incident raises questions over how the first phone call between New Zealand Prime Minister Bill English and Mr Trump will play out.

The Prime Minister's office received a letter from Mr Trump this afternoon; acknowledging the upcoming Waitangi Day and the close relationship between the US and New Zealand.

In it, Trump said he was looking forward to continuing to work together in the year ahead.