Mathieu Valbuena has spoken for the first time about how Karim Benzema allegedly encouraged him to pay blackmailers demanding money for a sex tape.

Valbuena’s fellow France international has been mis en examen – the French equivalent of being charged – accused of being part of the extortion plot.

In a further development, the French Football Federation, which until now has kept out of the sex-tape affair, insisting it was not damaging to the sport’s image in the run-up to France hosting the European Championship, announced on Friday it had lodged papers as a civil party to the criminal case.

Under French law this move enables the federation’s lawyers to have access to the case files and attend all hearings with a view to seeking damages.

Giving his first public comments on the affair, the Lyon midfielder Valbuena said Benzema had encouraged him to meet one of the alleged blackmailers. He admitted feeling “deeply disappointed” that someone he considered a friend and team-mate might be involved in the alleged plot.

“He wasn’t aggressive, and he didn’t speak to me firmly, directly about money, but when you insist that I meet someone … hmmm. Personally, I’ve never known of anyone willing to destroy a video for free just because they love me! You can’t take people for idiots,” Valbuena, 31, told Le Monde.

“Afterwards, he said several times that I was dealing with ‘big bandits’ and he added: ‘After all, the video is hot. If it was me, with my family and all … you’d have to be strong.’

“He would say: ‘I can introduce you to my friend …’ It kept coming back to that. Then when he was about to leave Karim said: ‘What shall I do? Shall I give him your number? Should I give you his number?’

“He was inciting me. He was saying, indirectly: ‘You will have to pay.’”

Valbuena said it was hard to take Benzema’s alleged involvement in the extortion attempt as he was a “friend in the French team”, adding: “I am very, very, very disappointed and I can only accept that my relations with Karim were not as sincere as he makes out.”

The Real Madrid striker has admitted involvement in the alleged extortion case, telling investigators he approached Valbuena about the tape on behalf of “a childhood friend” but claims he did not think he was harming the other player.

His lawyer, Alain Jakubowicz, said he would suggest Benzema give his own version of events to show “he is not the man they are making him out to be”.

Another lawyer, Sylvain Cormier, has insisted his client is innocent, saying: “He took no part, I state this again – no part – in the blackmail or blackmail attempts.”

Benzema’s alleged involvement came after police were alerted to the apparent blackmail attempt earlier this year and tapped the phones of several suspects.

Investigators summoned Benzema to answer questions after he allegedly mentioned the sex tape to Valbuena during a gathering of the France team at their Clairefontaine training base before Les Bleus met Armenia and Denmark in October.

Another French international, Djibril Cissé, was interviewed by police as part of the investigation in October, but was released without charge.

On his Facebook page, Valbuena wrote that he had “nothing to reproach Cissé for” and that Cissé had “behaved like a friend, trying to help me”.

In the interview with Le Monde, Valbuena explained that the video fell into the hands of the blackmailers after he changed his mobile phone. He had asked a man, known in football circles for supplying players with the latest phones and computers, to transfer the material on his old telephone to the new.

The investigation is continuing. Benzema has been banned from approaching Valbuena and neither player was selected for the France team to play Germany and England recently.

The Versailles prosecutor said the alleged crime of conspiracy to blackmail and participating in a criminal group for which Benzema was being investigated could carry a prison sentence of at least five years.

(Guardian Service)