Brian May has described the "joy" he feels at hearing former bandmate Freddie Mercury's voice as he works on releasing previously unheard Queen material.

Brian May revealed that he and drummer Roger Taylor were close to announcing new tour dates for the band.

Mr Taylor has previously hinted that Queen were planning to reunite with former American Idol contestant Adam Lambert for a project this year.

And, speaking in London today at the launch of a campaign to raise money for a badger vaccination initiative, Mr May said that the group were close to announcing new dates.

He also confirmed that a biopic of Freddie Mercury's life, starring Skyfall actor Ben Whishaw, was getting underway.

Mr May has previously revealed that he is working on a new Queen record which will feature at least three previously unheard tracks featuring Freddie Mercury on vocals.

Describing how it felt to be working on the material, he said: "When I hear Freddie's voice coming off the recording, it's 35 years ago but it feels as if it was yesterday, and he's full of beans and naughtiness. It's a joy.

"You can't live in the past, but I think it's important to keep an awareness of it, and a connection to it.

Mr May, who was given the all-clear for prostate cancer after a scare earlier this year, said that he was "busier than ever".

As well as continuing his campaign work for animal rights, he is also planning to tour with longtime collaborator Kerry Ellis in February for a series of concerts in the UK, Russia, Belarus and Malta.

Joking that he was struggling to find "time to sleep", he said: "We're incredibly busy right now. Forty years since Queen were formed, and over 20 years since Freddie died and we are busier than ever. 

"We're about to press the button on some touring, which I'm very excited about, and we have a film to make.

"I'm also involved with lots of books and my astronomy work, and campaigning for animal welfare takes up more and more time, so it's important for me to try to keep a balance."

Speaking in December, Roger Taylor implied that Queen were planning to reunite with Adam Lambert for a project, after a series of shows with the singer in 2012.

He said: "He's very theatrical. And he really interprets our songs just brilliantly. I feel he's going away from the pop thing which is good, I think. And he's becoming a serious player." 

"He's got a voice which is pretty unbeatable. I do think we will be working with Adam next year, yeah."

Following Mercury's death in 1991, the band also collaborated with singer Paul Rodgers, but amicably parted company with him in 2009.