U.S. President Barack Obama, speaking in France at commemoration ceremonies marking the 70th anniversary of the D-Day landings, has said the invasion by 150,000 Allied troops turned "more than the course of a war but the fate of human history."
He said that the United States' "commitment to liberty, our claim to equality, our claim to freedom and to the inherent dignity of every human being" was written "in the blood of these beaches and it will endure for eternity."
Obama said the D-Day landings during World War II forged a "beachhead" for a new democratic age.
He said that "the tide was turned in that common struggle for freedom" on D-Day and now lives on in a new generation.
Obama spoke from a cemetery containing the graves of almost 10,000 U.S. soldiers who died in the Allied invasion.
Earlier on June 6, flags flew at half-staff on Omaha Beach, while D-Day veterans from the U.S. 29th Infantry Division stood at attention at exactly 6:30 a.m., the moment on June 6, 1944, when Allied troops first waded ashore.
French President Francois Hollande, opening the ceremonies, said his country would never forget the sacrifices of the U.S. soldiers, adding that the two nations' friendship "affirms the strength of human rights in the face of hatred and tyranny."
People walk aboard ships set up on the beach in Arromanches prior to a joint French-Dutch D-Day commemoration ceremony on June 6, 2014.
French President Francois Hollande speaks during a French D-Day commemoration ceremony at the World War II memorial in Caen.
Britain's Prince Charles listens to the service during a British D-Day commemoration ceremony at Bayeux Cathedral.
Britain's Queen Elizabeth lays a wreath during the French-British ceremony at the British War cemetery in Bayeux.
People wearing World War II-era British uniforms stand in front of British flags in Asnelles.
U.S. President Barack Obama and French President Francois Hollande participate in the 70th French-American Commemoration D-Day Ceremony at the Normandy American Cemetery in Colleville-sur-Mer.
American veterans observe a minute of silence during a joint U.S.-French D-Day commemoration ceremony at the Normandy American Cemetery and Memorial in Colleville-sur-mer.
Russian President Vladimir Putin meets with German Chancellor Angela Merkel in Deauville, France on June 6, 2014.
Family members of Canadian D-Day veterans, currently-serving soldiers, and local citizens attend a ceremony outside The Queen's Own Rifles of Canada House in Bernières-sur-Mer.
U.S. President Barack Obama and French President Francois Hollande look out over Omaha Beach as they participate in the 70th French-American Commemoration D-Day Ceremony at the Normandy American Cemetery and Memorial in Colleville-sur-Mer.
In his speech, French President Francois Hollande paid tribute to "the courage of all these young men who came from all over the world to conquer -- meter after meter, inch after inch -- the beaches and the dunes."
He also paid tribute to the "courage of the Red Army" and the "decisive contribution" of the former Soviet Union in winning World War II.
Russian President Vladimir Putin also attended the Normandy events, along with the leaders of France, Germany, Britain, Canada, and Ukraine.
The events come amid a deep rift between Russia and Western states over Moscow's actions in Ukraine.
There are hopes the commemorations will spark a thaw in tensions.
On the eve of the commemorations, Hollande met separately with Obama and Putin in Paris.
The British and German leaders also used the events as a backdrop for separate meetings with Putin about the Ukraine crisis.
Putin and Ukrainian President-elect Poroshenko later met briefly on the sidelines of the D-Day anniversary events.
It was Putin's first meeting with Poroshenko since he was elected president of Ukraine on May 25.
Kremlin spokesman Dmitry Peskov said the two leaders agreed that hostilities must be stopped by both sides -- the Ukrainian armed forces and the insurgents.
He said both also stressed that the crisis can only be solved through peaceful political means.
Peskov said Putin and Poroshenko held their brief conversation along with Hollande and German Chancellor Angela Merkel.
Putin also held informal talks with U.S. President Barack Obama at the D-Day ceremonies.
Leaders of the Group of Seven (G7) leading industrialized nations, at a two-day summit in Brussels this week, urged Putin to engage with Poroshenko as a way to resolve the Ukraine crisis.
With reporting by AP, Reuters, and AFP