US President Joe Biden congratulates King Charles III, Camilla on coronation

Washington: US President Joe Biden congratulated King Charles III and Queen Camilla on their coronation Saturday, paying tribute to the "enduring friendship between the US and the UK."

The US president, who did not attend the ceremony in London, called the countries' relationship "a source of strength for both our peoples," in a tweet.

The United States was represented instead by First Lady Jill Biden, with the president tweeting that he was "proud" she could be there "for this historic occasion."

In an interview aired Friday, Biden said he would see the new monarch in July to talk in particular about the environment.

"We're going to be going to a NATO conference in Europe, and I told (Charles) I'd stop either on the way there or the way back, to discuss what he really is passionate about, the environment," Biden told MSNBC.

The annual NATO summit is scheduled to take place in Vilnius, Lithuania on July 11 and 12.

Biden called Charles in early April to congratulate him on his accession to the throne.