This is only middlingly Christmassy, inasmuch as it isn’t Christmassy at all, but it sounds it because it’s a 1930s standard with a lush musical arrangement, and it was once recorded by Bing Crosby, who is of course the Christmassiest singer of all, and also by Nat King Cole, who is of course the second Christmassiest singer of all (and as it happens there’s more Nat to come in a few days’ time). With a song as lovely as this you don’t need to make excuses, anyway, it’s just a joyful thing to listen to, ideally whilst roasting chestnuts on an open fire.
And the reason it fits into the Beatles theme is that this version is from Tony Bennett’s 2006 album Duets: An American Classic, recorded in celebration of Bennett’s eightieth birthday – yes, he did just turn ninety – and it features Paul McCartney, and I hope you enjoy it as much as I just have (three times in a row).