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
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
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.
Previous UN ambassadors such as Susan Rice and John Bolton had demonstrated experience and expertise before taking the job.
The child of Indian Sikh immigrants, Haley was born and raised in South Carolina. She worked in her mother's clothing store and attended Clemson University, where she graduated with an accounting degree.
She entered politics formally in the early 2000s and worked her way up to become a popular, two-term governor.