Does anyone know this war movie ?

iMax

I saw a war movie when I was a kid & for the life of me, I can't remember what it's called nor the actors in it. the only thing that really stuck with me was the closing scene which I'm going to describe in spoilers for obvious reasons:

The two British or American soldiers/spies are holed up in the cellar of either a bank or church, it was one of those old several feet thick walls buildings. They've managed to stave off attacks by the Germans for many hours.

The Germans have started to pump water into the basement to either flush them out or kill them & deciding that there is no other option they decide to kill themselves. However, they have only one bullet left & as the water rises to shoulder level, with the contents of the cellar floating around them, shivering & losing energy, they hug each other tightly, both of them hold the gun & they put their heads together.

The closing shot of the movie is an off screen shot ringing out, the German's reaction & one of their bodies floating.

I would have seen it about 25/30 years ago on VHS. As far as I know it's based on actual events & I'd love to see it again. Anyone know it's title so I can at least get closure on IMDB ?

TIA

philc

film is operation daybreak