Washington: King Charles III on Tuesday urged the United States and Britain to renew their historic transatlantic partnership, using both a speech to Congress and a White House state dinner to emphasise the enduring strength of ties between the two nations.

Speaking during a state dinner hosted by Donald Trump, the British monarch avoided direct reference to tensions between Washington and Keir Starmer, but underscored the importance of unity. He described the alliance as “indispensable,” noting that the two countries had “stood together in the best and worst of times.”

Earlier, in a rare address to the US Congress—the first by a British monarch since Queen Elizabeth II in 1991—Charles called on the US to remain committed to its Western allies. Marking 250 years since American independence, he stressed the need for “unyielding resolve” to secure a just and lasting peace in Ukraine amid its ongoing conflict with Russia.

He also highlighted shared democratic traditions, pointing to the enduring influence of the Magna Carta on American law and governance, including its citation in numerous US Supreme Court cases. Emphasising constitutional principles, he noted the importance of checks and balances in limiting executive power.

President Trump, who welcomed Charles and Queen Camilla with a ceremonial reception at the White House, praised the monarch’s speech and reaffirmed the “special relationship” between the two countries. “Americans have had no closer friends than the British,” he said.

The visit comes at a sensitive time, with policy differences over issues such as Iran and Ukraine. Still, both sides struck a conciliatory tone, highlighting cooperation in defence, intelligence, technology and trade.

High-profile guests at the state dinner included Tim Cook, Jeff Bezos, Jensen Huang and golfer Rory McIlroy.

The four-day visit, marked by ceremonial events and closed-door talks, blends pageantry with diplomacy as both nations seek to reinforce a partnership long seen as central to global security and economic stability.