The former Republican governor of South Carolina vowed there is a "new US UN."
Haley told reporters, "Our goal with the administration is to show value at the UN, and the way to show value is to show our strength, show our full voice. Have the backs of our allies and make sure our allies have our backs as well."
She then added, "For those who don't have our backs, we're taking names, and we will make points to respond to that accordingly."
There have been reports the Trump administration is prepared to demand major cutbacks in UN agencies and personnel in slashing Washington's financial contributions to the global organization.
France's envoy to the United Nations, François Delattre, emphasized he had "only good things to say" about Haley.
But in response to reports the new administration may seek funding cuts for crucial UN programs, Delattre gave an analysis of America's role at the international organization that demonstrated how dramatically the United States has pivoted since Trump's election.
"As France's ambassador to Washington in the early 2000s, my key message to the White House was basically, 'Let us breathe. Don't micromanage the world,' " he told reporters. "A few years later, our main message to the American administration is, 'Please stay committed to world affairs, because we need America.' "
Haley said, "This administration is prepared and ready to have me go in and look at the UN and everything that's working. We're going to make it better. Anything not working, we'll fix, and anything that seems obsolete and not necessary, we're going to do away with."
Haley declined to take questions, departing to present her ambassador credentials to the new UN Secretary-General Antonio Guterres.
Haley has been one of the few Trump appointees to sail through Senate confirmation hearings. A rising GOP star, she was approved this week with wide bipartisan support, 96-4.
She became the fourth member of President Donald Trump's Cabinet to be approved as Republicans and Democrats battle angrily over the pace of confirmations.
The first Indian-American female governor of South Carolina, Haley cemented her legacy in her home state by calling for and ultimately removing the Confederate flag from the statehouse grounds.
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While Haley fared well during her confirmation hearings, opponents cited her lack of experience in international affairs.
Indeed, as she arrived Friday for her first day at the United Nations, she has little experience on the world stage, and most of her positions remain unknown.
|Haley said the US will 'show strength' at the UN [Mike Segar/Reuters]|
US envoy Nikki Haley at UN: 'We're taking names'
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.
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.
Nikki Haley: US Is 'Taking Names' at the UN
Looks like Nikki Haley has been instructed to make the United Nations great again. America's new ambassador to the UN presented her credentials to Secretary-General Antonio Guterres in New York yesterday and told reporters that the Trump administration plans to overhaul the body and is "taking names" of those opposed to American policies, Al Jazeera reports. The goal 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," the former South Carolina governor said. "For those that don't have our back, we're taking names, we will make points to respond to that accordingly," she added.
Haley told reporters that this is a "time for action." "Everything that’s working we’re going to make it better. Everything that’s not working we’re going to try and fix," she said. "And anything that seems to be obsolete and not necessary we're going to do away with." Trump has repeatedly spoken of defunding the UN and according to a draft executive order obtained by the New York Times, the things it plans to do away with include 40% of voluntary funding to the UN, which is used for things like humanitarian aid in war zones. (Haley was approved by a 96-4 Senate vote this week despite her lack of foreign policy experience.)