That's the British National Anthem, not the Sex Pistols tune.
This take on "God Save The Queen" follows "Oh Susannah" and "She'll Be Coming 'Round the Mountain," all tracks to be featured on Americana, the June 5 album from Neil Young and Crazy Horse, the band's first LP together since 2003. Below you can listen to the track--especially that awesome guitar tone (!)--and watch its video, which is actually just old footage of the queen herself. [NME]