MADRID (Reuters) -- Armed separatist group ETA called on Saturday for political change in Spain's Basque country in a statement that failed to mention a much-rumored cease-fire, a Basque radio station said. ETA said "dialogue and negotiation are the only paths towards a solution of the conflict" and that the time had come "to make firm commitments and important decisions on the future of the Basque Country."

The statement, in which ETA also claimed responsibility for eight recent bomb blasts, was sent to radio station Euskadi Irratia and published on its Web site.

Basque groups should "take steps now, without waiting for anybody," ETA said.

ETA, which is included in lists of terrorist groups compiled by the United States and the European Union, has killed around 850 people since 1968 in its fight for Basque independence. The statement accused the moderate Basque nationalist party PNV and Spain's ruling Socialist party of trying to prolong the status quo with talk of expanded autonomy for the Basque region. ----No cease-fire

ETA made no mention of any cease-fire, despite rising media speculation this week that a breakthrough in the long-running conflict was imminent.

Mainstream political parties reacted with disappointment.

"This communique again frustrates hopes of peace," said Rodolfo Ares, a spokesman for the Basque wing of the Socialist Party. "We say again clearly and firmly to the terrorists and those who support them that democracy and the force of law will not pay a political price so that they will lay down their weapons." Leopoldo Barreda, spokesman for the conservative Popular Party in the Basque Parliament, said: "There is no change. The only possible decision is ... to combat ETA until finishing it off."

Speculation about a possible cease-fire has risen since Prime Minister Jose Luis Rodriguez Zapatero said this month that Spain could soon see the "beginning of the end" of ETA violence. Juan Jose Ibarretxe, PNV leader and Basque premier, said on Thursday he hoped ETA would announce a truce "in the near future", adding: "We must be prepared to take advantage of an opportunity that is going to present itself."

ETA previously called a full ceasefire in September 1998. The group rescinded the cease-fire in December 1999 and started killing again in January 2000.

ETA has continued bombing since then but its last fatal attack was on May 30, 2003 when a bomb killed two police officers and seriously injured a third in northern Spain.

Last May, Spain's Parliament endorsed an offer by Zapatero to negotiate with ETA if it gave up its campaign of violence.

He has been accused by the Popular Party of pandering to the separatists and he angered the families of ETA's victims last week by not attending a conference they had organized. He later admitted this had been an error.