PARIS -- King Charles III became the first British monarch to make a speech from France鈥檚 senate chamber on Thursday, praising the 鈥渋ndispensable relationship鈥 between the U.K. and its neighbour which he said was 鈥渁s firm as it has ever been.鈥

Charles and his wife, Queen Camilla, are on a three-day state trip to France, visiting Paris and Bordeaux, concluding Friday.

The 74-year-old sovereign was given an enthusiastic welcome to the chamber 鈥 receiving a standing ovation from parliamentarians as he entered. When his late mother, Queen Elizabeth II, visited in 2004, she made her speech from the adjoining Salle des Conferences.

Charles vowed that 鈥渇or the time that is granted to me as King鈥 he would seek to strengthen U.K.-French ties, adding that 鈥渢ogether, our potential is limitless.鈥

The King 鈥 whose speech came 231 years to the day since France abolished its own monarchy and established a republic 鈥 spoke of being 鈥渇lattered鈥 to have been invited to speak by the two presidents of the two houses that make up France鈥檚 parliament.

During his address, he saved some of his strongest words to rebuke Russia鈥檚 invasion of Ukraine, while also urging further action to tackle the climate crisis.

鈥淣ow, more than 80 years since we fought, side by side, for the liberation of Europe, we once again face unprovoked aggression on our continent,鈥 Charles told French lawmakers at the Palais du Luxembourg, where the French senate is located.

鈥淥ur alliance and our resolve are as important as ever. Together, we stand in resolute solidarity with the Ukrainian people. Together, we are steadfast in our determination Ukraine will triumph, and that our cherished freedoms will prevail.鈥

He continued: 鈥淭hese horrifying events have once more demonstrated the fragility of so much that we hold dear. Just as we stand together against military aggression, so must we strive together to protect the world from our most existential challenge of all 鈥 that of global warming, climate change and the catastrophic destruction of nature.鈥

Charles deftly flipped between French and English throughout his address, his joke warning against 鈥渓ow blows鈥 but wishing 鈥渕ay the best man win鈥 as France hosts the men鈥檚 Rugby World Cup eliciting laughter from around the room.

Earlier he鈥檇 been greeted at the Palais du Luxembourg by the senate and national assembly presidents before meeting representatives from both houses of French parliament and signing a visitors鈥 book in the Salle des Conferences.

On the other side of the River Seine, Queen Camilla was at the Bibliotheque Nationale de France, the national library, where she and the French president鈥檚 wife, Brigitte Macron, were launching a new Franco-British literary prize.

The royal couple were expected to reunite afterward and rub shoulders with top athletes at an event highlighting the advantages of sports for young people.

The first day of the trip, on Wednesday, was all about symbolism and pomp, featuring a highly formal ceremonial welcome at Paris鈥檚 Arc de Triomphe, a procession down the famed Champs-Elysee and talks at the presidential palace.

Later, Macron posted a video of the two leaders walking between the Elysee palace and the nearby U.K. ambassador鈥檚 residence on X, formerly known as Twitter. In the short clip, the two greeted crowds of well-wishers lining the streets amid shouts of 鈥渧ive le Roi鈥 鈥 or 鈥渓ong live the King.鈥

That evening, Charles and Camilla were guests of honour at an extravagant state banquet at the Palace of Versailles on the outskirts of the capital.

Actors Hugh Grant, Charlotte Gainsbourg and Emma Mackey, as well as Rolling Stones frontman Mick Jagger and former French football manager Arsene Wenger, were among the famous faces to add their star power to the glamorous black-tie soiree.

Up to 180 guests dined in the gilded Hall of Mirrors at the former royal residence, built by French King Louis XIV, enjoying a menu featuring blue lobster and crab cakes and Bresse chicken marinated in champagne with a cep mushroom gratin.

The rescheduled royal trip 鈥 which is taking place at the request of the British government and by invitation from the French 鈥 is being seen as a soft-power continuation of the U.K.鈥檚 efforts to reboot the Anglo-French relationship.

It follows U.K. Prime Minister Rishi Sunak鈥檚 own trip to Paris earlier this year for a bilateral summit designed to mend relations which have been strained since Brexit.