Nikki Haley, the new US ambassador to the United Nations, has said Donald Trump's new administration will push for an overhaul of the world body and bluntly warned those who oppose Washington's policies that she is "taking names".

Haley made brief remarks to reporters as she arrived on Friday at the UN headquarters in New York to present her credentials to Secretary-General Antonio Guterres.

"Our goal with the administration is to show value at the UN and the way that we'll show value is to show our strength, show our voice, have the backs of our allies and make sure that our allies have our back as well," Haley said.

"For those that don't have our back, we're taking names, we will make points to respond to that accordingly," added Haley, a former South Carolina governor with little foreign policy and no US federal government experience.

"Everything that is working, we are going to make it better. Everything that is not working we are going to try and fix. Everything that seems to be obsolete and not necessary, we're going to do away with," she said.

Haley held a 20-minute meeting with Guterres, who was "delighted to meet her," according to UN spokesman Stephane Dujarric.

"It was an introductory meeting and the start of engagement with the new US administration," he said.

During her confirmation hearing, Haley questioned whether the US was getting what it paid for with regards to the country's monetary contributions to the UN.

The US is by far the UN's biggest financial contributor, providing 22 percent of its operating budget and funding 28 percent of peacekeeping missions, which currently cost $7.8bn annually.

These are assessed contributions - agreed by the UN General Assembly - and not voluntary payments.

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UN agencies, such as the UN Development Programme, the children's agency UNICEF, the World Food Programme and the UN Population Fund, are funded voluntarily.

The White House is reportedly preparing an executive order that could deprive the United Nations of billions of dollars in US financial support.

Last year, Trump took to Twitter to disparage the 193-member world body after the US abstained in a December 23 Security Council vote, allowing the adoption of a resolution demanding an end to settlement building by US ally Israel.

Trump, who had called on President Barack Obama's administration to veto the resolution, warned that "things will be different" at the UN after he took office on January 20.  

Source: News agencies