UNITED NATIONS -  New US Ambassador Nikki Haley presented her credentials to UN Secretary-General Antonio Guterres on Friday, after vowing to overhaul the world body, while putting US allies on notice: "For those that don’t have our back, we’re taking names"

"This is a time of strength, this is a time of action, this is a time of getting things done," Haley said before going to the 38th floor for her meeting with the UN chief.

Born as Nimrata Randhawa to Sikh parents who migrated from Indian Punjab, Ms. Haley created history by becoming the first woman to occupy the governor's mansion of South Carolina.

Haley spoke to the news media immediately after she walked into UN headquarters for the first time, saying "it's a thrill to be here" and declaring that at the US Mission to the United Nations, "You are gonna see a change in the way we do business. It's no longer about working harder, it's about working smarter."

In the halls of UN headquarters, the Trump administration's approach to the 193-member world organization has been a subject of non-stop diplomatic discussion, speculation and concern.

Haley said President Donald Trump wants her to put "fresh eyes" on the United Nations.

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

Using blunt language, Haley outlined the new US approach to the United Nations.

"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, and 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," she said. "We will make a point to respond to that accordingly. But this is a time of strength. This is a time of action. This is a time of getting things done."

A United Nations spokesman said after the presentation of credentials, the new US ambassador had 20 minute meeting with the secretary-general. He said it was an essentially "get-to-know" meeting and the UN chief looks forward to more detailed conversation with her.

The United States is the largest contributor to the United Nations, paying 22 percent of the $5.4 billion core UN budget and 28 percent of the $7.9 billion UN peacekeeping budget. These are assessed contributions - agreed by the UN General Assembly - and not voluntary payments.

Last year, Trump took to Twitter to disparage the 193-member world body after the United States abstained in a Dec. 23 UN 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 United Nations after he took office on Jan. 20.