BARCELONA, Spain (Reuters Life!) - Coldplay frontman Chris Martin said on Tuesday the British band's new album was more "sexy" than the critically acclaimed "X&Y" that was released in 2005.

Joking with the press and appearing more relaxed than during sometimes tense exchanges with British journalists in recent days, Martin and his bandmates were in Barcelona to give a free concert ahead of a tour of North America, Japan and Europe.

Martin briefly walked out of a radio interview last week, accusing the host of "twisting" his words.

"I think we are definitely more handsome now than we were three years ago," Martin joked. "I think that's reflected in our music, it's much more sexy."

"Viva La Vida or Death And All His Friends" is the eagerly anticipated followup to "X&Y" and stormed to the top of the British album charts on Sunday. Its biggest commercial test, in the key U.S. market, comes this week.

"X&Y" sold an estimated 10 million copies worldwide, and if "Viva La Vida" can match that tally Coldplay's record label EMI will breathe a huge sigh of relief.

The label, taken into private hands in 2007, lost Paul McCartney and Radiohead in 2007 and could see the Rolling Stones leave in 2008, according to industry experts.

Martin, married to actress Gwyneth Paltrow, said Coldplay had been surprised at how personal some of the new album was.

"When you finish a big tour two things go through your head: one is may be we need to do the same thing again and again because the most people will like that.

"But after about two weeks, you forget that you've ever been popular, and so all the music you write becomes very personal and it's only now when we are releasing it that we realise how personal it is."

Reviews of "Viva La Vida" have been generally positive, and a free pre-tour concert in London on Monday night was also warmly received.

The band worked with renowned producer Brian Eno on their fourth album, after Eno volunteered to collaborate with them, according to drummer Will Champion.

"We wanted to find someone who had the same effect on us as Brian Eno did on U2 and David Bowie, and Talking Heads, all these incredible bands that we love.

"And so we asked Brian: 'Do you know anyone who could help us in the same way that you did?' And he said 'Well, I could, I wouldn't mind having a go.'"

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