Guterres working to make UN great again: Trump

US President Donald Trump, who has had an adversarial relationship with the world body, surprisingly showered praise on Secretary-General Antonio Guterres saying he was "working hard to 'Make the UN Great Again'".

The unexpected kudos in his tweet came after their meeting on Friday, which played off his election slogan of "Make America Great Again" and appeared to show a newly found appreciation that the world body could help Washington by dealing with conflicts after several developments that have highlighted the rift between Trump's US and the UN.

Trump's praise of Guterres was centred on monetary savings for the US as he added in his tweet, "When the UN does more to solve conflicts around the world, it means the US has less to do and we save money."

The UN has been at odds with Trump's world view with the General Assembly criticising Trump's decision to recognise Jerusalem as Israel's capital and move the US embassy there, Guterres opposing Washington's decision to withdraw from the Iran nuclear deal, and the UN failing to act jointly with the US against Syria.

The White House said that two of those issues -- Iran and Syria -- figured in the talks between Trump and Guterres.

A UN statement said: "The Secretary-General expressed his appreciation for the continued US engagement in the work of the UN."

The meeting with Trump capped two days of Guterres's diplomacy in Washington where he made rounds of Congressional leaders to try and revive the flagging support for the world body, especially with cuts in US contributions to the UN looming.

While neither the UN nor the White House gave details of who were at the talks, Trump's tweet included a photograph that showed them with Deputy Secretary-General Amina Mohammed, Permanent Representative Nikki Haley, Secretary of State Mike Pompeo and Trump's National Security Adviser John Bolton.

Trump also praised Haley, saying in the same tweet that she "is doing a fantastic job!"

She is credited with squeezing out $285 million out of the 2018-2019 UN budget of $5.4 billion, saving about $63 million for the US, which foots 22 per cent of budget.

The White House said they also discussed UN reform -- which is focused on saving even more -- and "the President reiterated his support for the Secretary-General's efforts to improve the efficiency and effectiveness of the UN".

Another topic in their discussions was North Korea, where Trump is hoping for a breakthrough in his upcoming talks with that nation's leader Kim Jong-un leading to Pyongyang's denuclearisation.

The UN statement said that they discussed the "broader situation" in the Middle East, without indicating if this week's Palestinian protests in Gaza during which more than 60 people were killed in firings by Israeli forces came up.

Guterres's Deputy Spokesperson Farhan Haq said that before the talks with Trump, he met with Pompeo and Bolton.

A former permanent representative, Bolton once said that if the UN headquarters building "lost ten stories, it wouldn't make a bit of difference".

On Thursday Guterres even had a meeting with the Freedom Caucus, a hardline right-wing group of Republican members of the Congress, who are very critical of the UN.