Spain's government said yesterday that a car bombing at Madrid airport blamed on Basque separatists ETA has ended the country's peace process.

Officials however believe that a weakened ETA is incapable of a sustained bombing campaign.

"ETA has broken, has liquidated, has finished the process," Interior Minister Alfredo Perez Rubalcaba told a news conference as rescuers using heavy lifters continued searching for the bodies of two men believed killed in Saturday's attack.

It was the strongest language by a government minister since the car bomb wrecked a multi-storey carpark at the ultra-modern Terminal Four of Madrid's Barajas airport.

ETA has not claimed responsibility for the bomb, but police said one of three callers making anonymous telephone warnings before the explosion identified him or herself as an ETA member.

Hours after the bomb, Prime Minister José Luis Rodriguez Zapatero suspended all efforts to seek dialogue with ETA, effectively ending a peace process he had started in June after the guerillas declared a ceasefire in March.

But Mr Zapatero's response was criticised by the conservative opposition Popular Party, which had opposed talks with ETA from the start and demanded the government now unequivocally declare the peace process dead.

"Obviously the process has finished," Mr Rubalcaba said, adding a barb for the opposition, "And now I've cleared that up, it would be fantastic if we could all work together to put an end to violence in Spain."

ETA killed over 800 people in four decades of violent struggle for independence for the Basque Country in northern Spain and southwest France. Its fight began during the Franco dictatorship when the Basque language and culture were suppressed but, in today's democratic Spain, only a minority of Basques want full independence, according to polls.