Irish rock star Bono praised Ukraine's fight for "freedom" during a performance in a metro station in downtown Kyiv Sunday, where the U2 frontman also issued his own prayer "for peace".
From the platform of a Kyiv metro station, the 61-year-old rock icon belted out U2 classics "Sunday Bloody Sunday", "Desire" and "With or without you".
"The people in Ukraine are not just fighting for your own freedom, you are fighting for all of us who love freedom," said Bono during a break.
The singer also referenced the past conflicts in the band's native Ireland and the troubles it had with a more powerful neighbour.
"We pray that you will enjoy some of that peace soon," said Bono.
The surprise appearance by Bono -- a long time humanitarian who frequently lends his voice to a variety of causes including the fight against poverty and AIDS -- came as air raid sirens echoed in the Ukrainian capital and fighting raged in the country's east.
At one point, Bono invited a Ukrainian soldier to sing along who called on the world's support for the embattled country as they covered "Stand by me".
Bono performed alongside U2's guitarist 'The Edge' to a small crowd of fans including fatigue-clad members of Ukraine's armed forces.
"It's some good emotions, that's all," said a member of the Ukrainian territorial forces in the audience.
"It's a strange feeling, like being a child going to first grade," said 36-year-old university lecturer, Olesia Bezsmertna, ahead of the show.