Defender Carles Puyol believes it will be "impossible" for him to recover from a knee injury in time to play for holders Spain at Euro 2012 starting next month.

"To be honest it's going to be very tough, but I have to wait and see how the operation goes," the Barcelona defender told a news conference on Wednesday when asked whether he would be fit for the tournament.

"But I think it's impossible because when you come out of an operation there is a recovery period and I believe that those who are in better shape should go," he added.

The loss of the talismanic Puyol, who is hugely respected by team mates and opponents alike, is a significant setback for the world and European champions, who begin the defence of their continental title against Italy on June 10.

His absence will likely mean that coach Vicente del Bosque will deploy Real Madrid's Sergio Ramos alongside Barca's Gerard Pique in central defence, with Javi Martinez of Athletic Bilbao another option.

Barca announced on Tuesday that Puyol had sustained an injury to his right knee that required arthroscopic surgery and would sideline him for around six weeks.

The shaggy-haired centreback damaged the knee in last weekend's La Liga match at home to Espanyol and is due to have the operation on Saturday.

He will be unavailable for the King's Cup final against Athletic Bilbao on May 25, the club said.

The 34-year-old has been a reliable presence in the Spanish back line for more than a decade, making 99 appearances and scoring the winning goal in the 1-0 semi-final victory against Germany at the 2010 World Cup.

"I am not saying I am retiring or not retiring from the national team," Puyol told reporters at Wednesday's news conference.

"Right now the operation is the important thing and later we'll see. It's not only my decision," he added.

Spain also face Ireland and Croatia in Group C at the Euro finals in Poland and Ukraine.

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