Queen guitarist Brian May has revealed that he was so taken aback by Adam Lambert's performance with the band in Ukraine last night (July 1) that he forgot how to play.

Lambert joined the classic rockers at a special gig in Kiev to promote the fight against AIDS, with Sir Elton John also performing.

The band played through a number of legendary songs such as 'Bohemian Rhapsody' and 'Under Pressure' as Adam Lambert gave Queen a 2012 twist.

Brian May later took to his official website to praise the singer and thank fans for attending the show. He said:

"Well, we did one! A show! And...well, it is out there in cyberspace already, spinning around the world. For a first show, I think, with all its train wrecks, it was a good first outing...I was at times quite mesmerised by what Adam was doing and sometimes forgot to play!! Ha ha."

He concluded: "Thanks to all the great folks who stood and rocked for many hours in Kiev's Freedom Square...you guys are the best."