John Lennon’s son Julian vowed he would never perform his father’s iconic peace anthem “Imagine.” He would only perform it if the world was ending, but the musician decided the world needed to hear his father’s words.

But due to the ongoing war in Ukraine the 59-year-old felt compelled to publicly perform the song as part of the 2022 Global Citizen’s Stand Up for Ukraine fundraiser.

Julian’s rendition was simple, yet just as powerful as his father’s song, which was released in 1971.

Julian wrote that the “unimaginable tragedy” in Ukraine prompted him to “respond in the most significant way I could.”

“The song reflects the light at the end of the tunnel, that we are all hoping for…” he wrote. “As a result of the ongoing murderous violence, millions of innocent families, have been forced to leave the comfort of their homes, to seek asylum elsewhere.”

More than 4.5 million refugees have fled Ukraine since the start of the war at the end of February.