Who will represent the USA at the B9 Summit in Bucharest, after Donald Trump refused the invitation
Thomas DiNanno, American undersecretary of state, will be present at the Bucharest 9 (B9) Summit on May 13 in the capital of Romania, official sources have confirmed for HotNews. A senior US official will also participate in the talks, but via video conference, according to the sources.
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 Assistant 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.
