When Fred Harris last saw Hugh Beach, he was dragging him, shot and temporarily paralysed, onto the back of his armoured car and to safety under a hail of German bullets.

Now, almost 70 years on, having not seen or heard from each other since, the pair have come together for an extraordinary reunion to share a beer and talk about the fateful events at the La Bassee canal crossing, in Nazi-occupied northern France, on September 3, 1944.

The actions of Driver Fred Harris and his fellow soldier Sergeant Bill Tynan that afternoon undoubtedly saved the life of the then-Lieutenant Beach, who would go on to become a General in a 40-year military career and be knighted by the Queen.

All three members of the 621 Field Squadron (Royal Engineers) had been sent in an armoured Morris Scout Car to find out whether or not the bridge was fit for tanks, when Lieutenant Beach, who had left the vehicle, engaged a group of German soldiers.

His Sten submachine gun jammed and he was shot in the spine as he attempted to crawl back to the vehicle, leaving him bleeding heavily.

Without a thought for their own safety, Sgt Tynan and Driver Harris called for covering fire before finding their comrade and dragging him back to their car and to safety.

Harris, of Featherstone Road, Mill Hill, and Beach, who lives in Earls Court, were in their early 20s at the time of the ill-fated reconnaissance mission – neither knows what became of Sgt Tynan - but now, at the age of 90, General Sir Beach was finally able to buy his former military colleague a pint and say thank you when they met again at the Victory Services Club in Marble Arch on Wednesday.

Now a grandfather-of eight, he said: “I remember the event vividly – like it was yesterday. I was about 100 yards from the bridge and at that moment, fatally, I saw two Germans pottering about.

“The nonsense thought crossed my mind that I had better engage them but of course my gun jammed after just two rounds.

“I thought I had better back out and got down on my hands and knees behind a railway line, but unfortunately my backside was too high and a bullet grazed my spine. I was left paralysed, useless, hopeless.

“Bill Tynan found me and I told him I wasn’t a lot of use but thankfully Fred was very bright and arranged for covering fire before they dragged me onto the back of the car. He was clearly a much greater tactician than I was.

“From that moment my memories are very episodic, but I know that when I was back on the car I was able to pass on the message that the bridge was intact and safe to cross.”

Lieutenant Beach was taken to a French hospital in a nearby town where he recovered for a few days as his father, a Major General in the Army himself, wrote letters of thanks to the heroes who saved his son’s life.

The General would go on to receive the Military Cross for bravery at the age of just 21 because of his actions at the bridge. But Driver Harris received no medals - only a mention and a certificate from Field Marshall Bernard Montgomery.

On Wednesday, at the ornate headquarters of the Victory Services Club, the war veterans were joined by Driver Harris’s daughter Claire and General Sir Beach’s son Michael.

The General brought with him the original letters of response from both of his life savers, as well as the doctor’s notes from his stay at the French hospital, detailing his treatment and condition.

Driver Harris, now 91 and with five great grandchildren, still has his copy of Major General Beach’s letter, and various mementos from his own Army career that ended in 1946 before he enjoyed a 40-year stint as the sports editor at the Hendon Times.

Speaking about meeting the man he saved for the first time in almost seven decades, he said: “It has been overwhelming. Neither of us would have ever thought we would see each other again.

“Clearly I should have stuck with him as he’s gone on to great things. I’m just absolutely delighted to see him in such good health and with a smile on his face.”

The historic reunion marks a “closing of the loop” for both men, according to General Sir Beach, who said he has been looking forward to being reunited with his Army colleague since they first made contact thanks to his son’s research on an Army veterans’ website last year.

He said: “There has been great excitement, huge excitement. It is a great closing of the loop and a pleasure to meet him again after all these years. It was an enormously heroic act, to which I undoubtedly owe my life.”