Heroes of the liberation of Europe were joined by a host of world leaders yesterday as tens of thousands of people paid tribute to the courage of servicemen on the 60th anniversary of D-Day.

British veterans proudly took part in commemorative events in northern France as they honoured comrades lost in the pursuit of freedom.

Others made personal pilgrimages to sites throughout Normandy to recall their memories of friends who never returned from the battleground.

The weekend's events marked the final time most of the men will return to the stretch of French coastline where they fought the bitter battle that helped free Europe from Nazi tyranny.

Last night, former soldiers, sailors and airmen paraded in front the Queen as anniversary events reached a poignant and moving climax on the seafront of Arromanches, where many British troops had come ashore in 1944.

In the evening sunshine, about 900 veterans, dressed in their military berets, blazers and regimental ties, marched past the Queen and the Duke of Edinburgh, who returned their salute.

In a heartfelt tribute to the veterans, many now in their 80s and 90s, the Queen said: "Thank you on behalf of the whole nation."

With thousands of local people, soldiers and visiting dignitaries looking on, the Queen added: "Their sacrifice must never be forgotten.

"What for you is a haunting memory of danger and sacrifice one summer long ago is for your country and for generations of your countrymen to come, one of the proudest moments in our long national history.

"I take it upon myself to express the immense debt of gratitude we owe to you all."

Some 156,000 Allied troops landed on the five invasion beaches on June 6, 1944.

It was an operation which wartime Prime Minister Winston Churchill described as "undoubtedly the most complicated and difficult that has ever taken place".

The invasion marked the beginning of an 80-day campaign to liberate Normandy which involved three million troops and cost the lives of 250,000.

Earlier yesterday, in a stirring international ceremony close to the Gold landing beach, French President Jacques Chirac presented the Legion d'Honneur medal to representatives of the Allied Nations of the Second World War.

Following a 21-gun salute from the French frigate Cassard, a total of 142 Allied veterans received thunderous applause as they led a parade before a host of heads of state.

Fourteen of the veterans - one each from Britain, the US, France, Belgium, Australia, Canada, Greece, New Zealand, Poland, the Czech Republic, Slovakia, the Netherlands, Norway, and Luxembourg - remained on the parade ground to receive medals from President Chirac.

British veterans attending the ceremony were deeply moved.

Tears came to the eyes of Benjamin Gamble, 77, of Darlington, as he recalled his experiences 60 years ago.

"I was the youngest Brit in Normandy on D-Day, just 17 years old," he said.

"I ran away from home to join the Royal Marines. I had my own landing craft, slung onboard the troop ship Glenear, and when we arrived I ferried men to and from the shore with German shells exploding all around me.

"The noise was tremendous. I'm still virtually deaf from it today.

"I've shed a few tears this weekend. I lost so many friends."

The Queen, Prime Minister Tony Blair, Mr Chirac, US president George Bush and Russia's Vladimir Putin were among those who gave the heroes a spontaneous standing ovation.

And for the first time, Germany was represented by its leader at the official ceremony.

Chancellor Gerhard Schroeder said the invitation proved that the shadow of war had finally been lifted from his country.

Mr Chirac said: "We hold up the example of Franco-German reconciliation to show the world that hatred has no future, that a path to peace is always possible."

In her first engagement of the day, the Queen had paid tribute to Canadian veterans in a ceremony in the French seaside village of Courseulles-sur-Mer overlooking Juno beach, one of the five D-Day landing points.

Nearly one in ten of the soldiers who stormed Normandy's beaches during Operation Overlord was a Canadian.

Mr Bush joined Mr Chirac for a ceremony at the massive US cemetery in Colleville, which holds the remains of 9,386 men, many of whom died in the fiercest fighting of D-Day on Omaha beach. In a moving speech, Mr Bush said their sacrifice threw back the "marching mechanised evils of fascism".

He praised the strength of the US's alliance with Europe, saying that unity in the cause of freedom was strong but "still needed today".

Mr Chirac dubbed the US the "eternal ally" of France, pledging that the country would never forget the "day hope was reborn and rekindled".

The area of the original invasion of Normandy had earlier been sealed off, with 17,000 military and police personnel barring all unauthorised access by land and sea and Mirage fighter jets on standby to fend off any attempt to breach an air exclusion zone around the sites of commemorations.

In Bayeux, Mr Blair and wife Cherie joined the Queen and Mr Chirac at a joint British-French service at the Commonwealth War Graves Commission cemetery, where about 4,200 troops are buried.

The Queen and Mr Blair met former soldiers, sailors and airmen who joined 12,000 people to pay tribute to the bravery of Allied troops.

With the glinting medieval spires of Bayeux cathedral as a backdrop, a bugler sounded the Last Post and the massed congregation paused for a minute's silence, many overcome with emotion.

Many assembled on the manicured lawns of the Bayeux cemetery among row upon row of white gravestones, while others visited the town's memorial, which commemorates the death of 1,801 men.

Yesterday morning, at Sword beach, veterans looked on as the sand was covered in a sea of 70,000 Union flags.

Each bore a handwritten tribute to the young men cut down in fierce fighting and the event will raise £1m for the Royal British Legion.

Tears welled in the eyes of scores of former troops as they read the words that had poured in from across Europe.

One read simply: "We are here now because you were there then."