U.S. President Donald Trump and French President Emmanuel Macron attended a ceremony Thursday at the American Military Cemetery in Normandy to mark the 75th anniversary of D-Day, following with a bilateral meeting in the city of Caen.

Ceremonies have been taking place at other cemeteries and monuments across the region as the U.S., France, Britain, Canada and other Allied nations pay tribute to the fallen.

About 2,500 U.S. troops died in a single day on June 6, 1944, as Allied forces invaded Nazi-occupied France. Total Allied casualties that day are estimated at 10,000. Less than a year after the invasion, officially named “Operation Overlord,” Germany surrendered as Berlin fell to the Allies.

The 75th anniversary was marked at dawn on Omaha Beach, below the U.S. cemetery. American D-Day veterans were among the crowd that had gathered to greet the sunrise with a minute’s silence.

President Trump and French President Macron arrived by helicopter several hours later. Seated in the front row, the D-Day veterans were given repeated standing ovations by the thousands-strong crowd. The French president spoke first.

“We know what we owe to you, veterans, our freedom. On behalf of my nation, I just want to say thank you,” Emmanuel Macron told the veterans in English.

Turning to his American counterpart, he spoke pointedly of the alliance between nations underpinning victory and freedom.

“The United States of America, dear President Trump, is never so great as when it fights for the freedom of others,” said Macron.

President Trump continued the tribute to the fallen and to the veterans present at the ceremony, saying they had saved not only a nation, but a civilization.

“To the more than 170 veterans of World War II, who join us today, you are among the very greatest Americans who will ever live. You are the pride of our nation, you are the glory of our republic, and we thank you from the bottom of our hearts. Today we express our undying gratitude, when you were young, these men enlisted their lives, in a great crusade, one of the greatest of all times,” Trump said, before paying tribute to the shared sacrifice among allies.

“Our cherished alliance was forged in the heat of battle, tested in the trials of war, and proven in the blessings of peace. Our bond is unbreakable,” Trump said.

U.S. General Dwight Eisenhower was the Supreme Commander of Allied Expeditionary Forces on D-Day. That post, now known as Supreme Allied Commander Europe, is currently held by General Tod Wolters, who also attended the ceremony Thursday. Despite transatlantic political tensions, he told VOA the alliance with Europe is in good health.

“Take a look at what took place on Utah Beach, the cooperation between multiple nations and multiple domains,” said Wolters. “And all you have to do is put your feet on the sands and you get a deep appreciation for how powerful the alliance is and the importance of keeping that alliance together. And today I feel very, very confident that the alliance is a strong as it’s ever been.”

European leaders have repeatedly praised America’s sacrifice, hoping to underline to President Trump the importance of the transatlantic bond at a time of heightened tension and fears over the future of the alliance.

Following the ceremony, Trump and Macron held a bilateral meeting in the nearby city of Caen, where NATO, trade and defense issues were expected to feature high on the agenda.