Paul McCartney (L) and Ringo Starr of The Beatles perform onstage during the 56th GRAMMY Awards at Staples Center on Jan. 26, 2014 in Los Angeles.

Paul McCartney got a little help from his friends when he played London’s O2 Arena on Sunday night with Ringo Starr and Ronnie Wood in support.

McCartney and Starr formed a rare Beatles mini-reunion as they hit their classic “Get Back” with Wood, of the Rolling Stones and the Faces, on guitar. The impromptu performance happened during the encore and can be seen below.

Having a great time at the O2 London freshen up tour With Paul Ronnie and Ringo a great night love you man peace and love. --??------------------?? pic.twitter.com/IJUDO1eI9M — #RingoStarr (@ringostarrmusic) 17 December 2018

Wow. Ringo Starr and Ronnie Wood join Paul McCartney on stage for a historic moment at @TheO2 #UnforgettableGig pic.twitter.com/L9lo1QLJ1I — O2 music (@O2music) 16 December 2018

On his Freshen Up tour, McCartney draws from his solo career, along with tracks from the Beatles and Wings, and on Sunday night he dusted off his timely tune, "Wonderful Christmastime."

Earlier this month, McCartney added four U.S. stadium dates to the U.S. leg of his 2019 jaunt, which now numbers 12 shows.

The Freshen Up tour is in support of McCartney’s latest studio album, Egypt Station his first No. 1 debut on the Billboard 200 in over 36 years.