Darryl Nirenberg was sworn in as the United States’ new ambassador to Romania on Thursday.

“The United States Embassy in Bucharest looks forward to working under his leadership to further deepen the strong and enduring partnership between the United States and Romania,” the US Embassy wrote in a social media post.

Nirenberg will officially assume his duties after presenting his letters of credential to Romanian President Nicusor Dan.

He has nearly four decades of experience in foreign policy and legislative affairs and previously served in senior advisory roles within the US Senate, including work linked to the Senate Foreign Relations Committee, where he was involved in shaping US positions on international issues.

Before his diplomatic nomination, he was a partner at a Washington-based law firm specializing in government relations and public policy.

His appointment comes as Romania, a NATO and EU member, watches developments with the war on its border which is now in its fifth year.

Romania has a strategic partnership with the United States and many Romanians are pro-American. But there is also concern about the potential spread of Russian aggression in the event of a Trump-Putin peace deal that is favorable to Russia.

Bucharest’s pro-Western government has allied itself with European states which want security guarantees to prevent a fresh outbreak of hostilities on the continent. 

US President Donald Trump announced Nirenberg’s appointment in May 2025.

“He will help us strengthen our ties with Romania, support our military partnership, and promote and defend America’s economic and security interests abroad,” Trump said then.

During his confirmation process, Nirenberg underlined Romania’s strategic importance as a NATO ally on the Black Sea and emphasized continued cooperation on defense, energy security and trade.

He succeeds Kathleen Kavalec, a US State Department employee, who left the post after Trump was re-elected.

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