The Beatles on Thursday released a new song, “Now And Then," their first track in 27 years, according to an announcement by the English band’s publishing agency Universal Music Group on Friday.

According to the agency, “Now And Then” will be the last song in which all the members of The Beatles participated in its production. Before the release of "Now And Then," the last song released by the group was "Real Love" in 1996.

"Now And Then" was first written and sung by the band's lead-vocalist and rhythm guitarist John Lennon in 1977, when he recorded a demo. After his death in 1980, his widow Yoko Ono handed over the recording to the remaining members of The Beatles in 1994.

Paul McCartney, George Harrison and Ringo Starr attempted to complete "Now And Then," adding more instruments and new choruses but they failed as the quality of the original recording was too poor. They couldn’t exclusively lift Lennon’s voice from the background instruments due to technological difficulties.

During the making of "The Beatles: Get Back" documentary, however, director Peter Jackson’s film company developed an artificial intelligence software to "de-mix” recordings of the overlapping sounds, according to the Universal Music Group.

In McCartney's words, Lennon's voice is "crystal clear" on "Now And Then."

"Now And Then" is available on various streaming services including Spotify, Apple Music and Amazon Prime Music. The song also will be included in the remastered version of the "Red" and "Blue" greatest hits albums to be released on Nov. 10.

The "Red" and "Blue" greatest hits albums, officially titled "1962–1966" and "1967–1970" respectively, are a compilation album of songs by The Beatles, covering the songs of the years indicated in the title.