Official: Who from the Trump Administration will represent the US at the B9 Summit in Bucharest
American Undersecretary of State Thomas DiNanno will come to Romania next week and will be present at the B9 Summit that is being held in the Capital on May 13, the US Embassy in Bucharest announces.
The embassy's announcement confirms the information previously disseminated by HotNews according to which Undersecretary of State for Arms Control and International Security Thomas DiNanno will be the one to represent the Washington administration at the B9 Summit in Bucharest, after President Donald Trump declined the invitation.
Official sources also told HotNews that a senior American official will also participate in the talks, but in videoconference format.
The United States Embassy in Romania informed on Friday in a statement that the US Undersecretary of State for Arms Control and International Security, Thomas G. DiNanno, will pay a visit to Warsaw (Poland), Bucharest (Romania) and Tallinn (Estonia) from May 11-15, 2026.
According to the press release, in Romania, “Undersecretary DiNanno will represent the United States at the Bucharest 9 (B9) Summit of the Eastern Flank of NATO and the Nordic Allies”.
“In Poland, Under Secretary DiNanno will meet with senior Polish government officials to discuss defense and civilian nuclear energy cooperation. Under Secretary DiNanno will also meet with representatives of US industry to discuss EU defense protectionism, the 'America First' arms transfer strategy, foreign military sales reform, co-production and defense innovation.” And “in Estonia, Under Secretary DiNanno will meet with senior Estonian government officials and participate in the Lennart Meri Conference,” the US embassy said.
Who is Thomas DiNanno?
Thomas DiNanno became Under Secretary of State for Arms Control and International Security on October 10, 2025, according to the description on the official website of the US State Department.
Previously, he served at the agency as deputy secretary and senior official of the Office of Arms Control, Verification and Compliance (AVC), where he directed foreign policy for nuclear arms control, strategic stability, missile defense, and outer space.
The US official has been leading negotiations with Russia on the New START nuclear arms reduction treaty in 2020, as well as discussions on other US deterrence commitments with Japan, South Korea and Australia.
Even before his 2025 nomination, Under Secretary of State DiNanno led nuclear deterrence and resiliency strategies for the US Strategic Command at the National Institute for Strategic Studies, according to the description on the institution's website.
Donald Trump declined Romania's invitation
HotNews wrote on April 6 that the American president declined the invitation to come to Bucharest for the B9 Summit.
A day later, President Nicușor Dan provided details of Trump's response, saying that Romania received “a diplomatic letter thanking us for the invitation, thanking us for the collaboration we have, including allowing access to American technicians and soldiers to the Kogalniceanu base and Turzii Plain.”
The B9 format was launched in 2015 by the presidents of Romania and Poland at the time, Klaus Iohannis and Andrzej Duda, in the context of the annexation of the Crimean Peninsula by Russia, as a platform for consultation and coordination of the positions of NATO countries on the eastern flank.
The most recent B9 summit took place in Vilnius, Lithuania, and Nicușor Dan also participated in the event. At that time, Mark Rutte, the Secretary General of NATO, and Ukrainian President Volodymyr Zelensky were also present in the capital of Lithuania.
The last B9 summit held in Bucharest took place in 2022, a few months after Russia attacked Ukraine.
