Kelly Craft, President Donald Trump's new ambassador to the United Nations, began her duties on Thursday, vowing to defend the interests of the United States while working with allies to resolve global conflicts.
Ms Craft's arrival comes little more than a week before the high-level annual UN General Assembly and ends almost nine months of the US having no permanent representative at UN headquarters in New York.
After formally presenting her diplomatic credentials to UN Secretary General Antonio Guterres she told reporters she was not only Mr Trump's emissary but “a voice of America's unwavering commitment to democracy, freedom, human rights and, whenever possible, the peaceful resolution of conflicts”.
“In a world marked by humanitarian crisis and geopolitical challenges, strong American leadership is absolutely critical and I intend to provide it,” she said.
The UN is currently grappling with wars in Syria, Yemen and Libya. Diplomacy in all three countries is deadlocked because of disagreements between leading powers in the UN Security Council and continued fighting on the ground.
“I will defend America's values and interest. I will stand by our friends and allies. I will advocate for the poor and weak,” said Ms Craft. She replaces Nikki Haley, who left the UN in December last year.
Unlike her predecessor, Ms Craft will not have a full seat in the US Cabinet. She will report to Secretary of State Mike Pompeo.
The UN role, considered a top job in past US administrations, was downgraded this year by John Bolton, the former national security adviser who left the Trump administration on Tuesday.
Managing the US presence at the General Assembly, the main week of which begins on September 23, will be Ms Craft's immediate challenge.
Mr Trump will address the annual gathering on September 24, where his hardline policy on Iran following his administration's exit from the 2015 nuclear deal with Tehran is expected to dominate. The US president has said he is open to talks with Hassan Rouhani, the Iranian president, but Tehran insists that sanctions re-imposed by Washington over the past 18 months must be lifted first.
