Royal protocol is more casual than it used to be.

King Charleswelcomed United States PresidentJoe Bidento Windsor Castle on Monday for the two men’sfirst formal meetingof the new royal reign. Inside the royal residence’s Green Drawing Room, King Charles and President Biden were briefed on the Climate Finance Mobilisation Forum’s discussions about how to better encourage big business and private finance to help counter the climate crisis.

When Biden’s car arrived at Windsor Castle, King Charles greeted him with a handshake. They then made their way up a few stairs to a platform to watch a band play both countries' national anthems and inspect the Welsh Guards.

Chris Jackson - WPA Pool/Getty Images

King Charles III and The President of the United States, Joe Biden walk together in the Quadrangle at Windsor Castle

President Joe Biden puts his hand on King Charles at Windsor Castle on July 10.CHRIS JACKSON/POOL/AFP via Getty

US President Joe Biden places his hand on the back of Britain’s King Charles III as they walk in the Quadrangle

CHRIS JACKSON/POOL/AFP via Getty

However, a Buckingham Palace source confirms King Charles was “entirely comfortable” with Biden touching the monarch on the back. “What a wonderful symbol of warmth and affection it was between both the individuals and their nations,” the source says.

The source adds that — despite some claims to the contrary — it was in keeping with the correct protocol that the President, 80, walked in front of the King, 74, during the inspection of the Guard of Honor.

President Joe Biden and King Charles at Windsor Castle on July 10.Ian Vogler - WPA Pool/Getty Images

King Charles III and US President Joe Biden review a guard of honour at Windsor Castle

Ian Vogler - WPA Pool/Getty Images

Biden and King Charles have met a number of times before, including a 2015 meeting in the Oval Office of the White House with then-PresidentBarack ObamaandQueen Camilla(who was then known as the Duchess of Cornwall) to theCOP26 United Nations Climate Change Conferencein 2021.

The meeting between King Charles and President Biden comes two months after the monarch’sMay coronationin London. Though Biden did not attend the crowning ceremony at Westminster Abbey — no American president ever has, according to theBBC! — his wife, first lady Dr.Jill Biden, was part of the congregation. She attended the historic church service with her granddaughter Finnegan Biden and chatted withKate Middletonat a specialBuckingham Palace receptionfor overseas guests on coronation eve.

The Bidens also attended Queen Elizabeth’s funeral in September.

King Charles and President Joe Biden at Windsor Castle on July 10.JONATHAN BRADY/POOL/AFP via Getty Images

US President Joe Biden and Britain’s King Charles III listen to the US national anthem before inspecting a guard of honour, formed by members of the Welsh Guards, during a ceremonial welcome in the Quadrangle at Windsor Castle

JONATHAN BRADY/POOL/AFP via Getty Images

But a U.S. state banquet may occur in the near future — in April, the White House said that Biden accepted the King’s invitation for a state visit during a phone call ahead of the coronation.

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Earlier on Monday, Biden met British Prime Minister Rishi Sunak. From the U.K., the president will travel to Lithuania for the NATO Summit and Finland for a U.S.-Nordic Leaders Summit, the White House said.

source: people.com