Amid diplomatic tension between the U.S. and the U.K. over the war in Iran, President Trump spoke about the "special relationship" between the two nations.

"In the centuries since we won our independence, Americans have had no closer friends than the British," Trump said. "We share that same root. We speak the same language, we hold the same values, and together, our warriors have defended the same extraordinary civilization under twin banners of red, white and blue."

"What a beautiful British day this is," President Trump said as he kicked off remarks with thousands of guests gathered outside the White House South Lawn on a rainy morning in Washington.

The royals' state visit is to mark the 250th anniversary of American independence from Great Britain.

"Honoring the British king might seem an ironic beginning to our celebration of 250 years of American independence, but in fact, no tribute could be more appropriate," Trump said. "Long before Americans had a nation or a Constitution, we first had a culture, a character and a creed."

President Trump and King Charles are now reviewing the troops gathered at the White House, after performances by the U.S. Marine Band of "God Save the King" and "The Star-Spangled Banner."

King Charles and Queen Camilla have arrived at the South Portico of the White House for a formal state arrival ceremony. They are being greeted by President Donald Trump and first lady Melania Trump.

Notable officials are gathered on the White House South Lawn in rainy weather for the ceremony that will include a review of the troops, remarks by Trump and more.

Charles and Camilla’s first stop in New York City Wednesday was the National 9/11 Memorial, where they met with families of Sept. 11, 2001, victims and first responders.

The royals were greeted by former New York City mayor Michael Bloomberg, who showed them the memorial and stood by their side as they laid a bouquet of flowers.

The flowers were accompanied by a note that read, “We honour the memory of all those who so tragically lost their lives on 11th September 2001, and stand in enduring solidarity with the American people in the face of such profound loss. Charles R Camilla R," according to reporters who are traveling with the king and queen.

Other elected officials in attendance at the memorial were New York City Mayor Zohran Mamdani, New York Gov. Kathy Hochul and New Jersey Gov. Mikie Sherrill.