Spain’s prime minister has appealed for calm ahead of planned peace talks in the Basque country. Jose Luis Rodriguez Zapatero spoke out during a visit by Argentinean president Nestor Kirchner to Madrid. It is the prime minister’s first official reaction to a veiled threat by the Basque terrorist group ETA on Wednesday.“We need as much political will as possible for the start of the talks,” he said. “As I have said before, it will be a long process. Bearing this in mind, I think the best advice is to keep calm.” In a statement posted on the internet, ETA warned that violence could flare if the Spanish government didn’t stop its so-called “oppression” – a reference to the recent arrests of ETA suspects in Spain and France. The group nevertheless added it would stand by its three-month old ceasefire. The right-wing opposition has lashed out at the government. Leader Mariano Rajoy said: “ETA tells the government what to do, says it must live up to its commitments. I hope the government has not made any deal the ETA terrorists.” Earlier this week, Spanish and French police arrested 12 suspected ETA guerrillas in the biggest operation against the Basque separatists since the ceasefire was declared.