Royal Air Force Lancaster bombers had much longer range and with a higher bomb capacity than the Yanks B-17's so presumably could have carried out strikes on Auschwitz. Such missions (it would have required multiple missions) would however have incurred unsustainable aircraft / aircrew losses with little military benefit. Greater utility was gained in the RAF raids on western German cities that helped degrade the Nazi war machine although this sadly resulted in the deaths of hundreds of thousands of German civilians (sometimes as many as 50,000 in one night) and of course many many slave workers as well. A war crime certainly but it did hasten the end of the war. I agree with others here that it would have been wrong to bomb people in Auschwitz who would actually go on to survive and be liberated. I can fully understand Ben Gurion's sentiment but life is precious and not to be taken lightly.
U.S. Democratic Senator Merkley airs support for Iran nuclear deal (Reuters)
from the article: Study: Ben-Gurion changed his mind on Allied bombing of Auschwitz