The armed group said in a statement ETA would resume its campaign "on all fronts," El Pais reported online citing Basque newspapers.
Spanish Prime Minister Jose Luis Rodriguez Zapatero conceded at the beginning of 2007 the peace process with ETA was not proceeding as he had hoped.
For three decades, ETA militants have been fighting for a Basque homeland along the French-Spanish border. Their attacks have claimed some 850 lives.
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