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The US Senate confirmed Bridget Brink as ambassador to Ukraine late on Wednesday night, filling the post as the US begins returning diplomats to the capital Kyiv.
Ms Brink received unanimous approval from a Senate committee for the post earlier on Wednesday, and was also confirmed unanimously by the full Senate without a formal roll-call vote.
The foreign relations committee held the veteran diplomat's confirmation hearing on May 10, only two weeks after she was nominated to the post by President Joe Biden.
Ukraine welcomed the Senate's confirmation of Ms Brink, President Volodymyr Zelenskyy's chief of staff said on Thursday.
"We greet the US Senate unanimous decision to approve Bridget Brink [as] the US Ambassador to Ukraine," Andriy Yermak wrote on Twitter.
The US evacuated its diplomatic staff from Kyiv three months ago as Russia invaded Ukraine but on Wednesday the embassy reopened. The return to Kyiv came weeks after Ukrainian forces defeated Moscow's efforts to take control of the capital.
"The Ukrainian people, with our security assistance, have defended their homeland in the face of Russia's unconscionable invasion and, as a result, the Stars and Stripes are flying over the embassy once again," Secretary of State Antony Blinken said in a statement.
The ambassador’s post has been vacant since former president Donald Trump abruptly forced out ambassador Marie Yovanovitch in 2019. She later became a crucial figure in the first impeachment proceedings against Mr Trump.
US Senator Bob Menendez, chairman of the Senate Foreign Relations Committee, said in a tweet that he was "proud to lead the Senate's swift confirmation" of Ms Brink to the ambassadorship.
Senate Majority Leader Chuck Schumer said in a separate tweet: "She is an excellent choice to lead our diplomatic mission as we continue standing with the Ukrainian people."
Ms Brink, a Michigan native who speaks Russian, had been the ambassador to Slovakia.
Agencies contributed to this report
