The state weather and environment services have faced intense scrutiny over their response to the October 29 disaster that wreaked widespread destruction and killed 227 people.

The European Parliament has blocked Teresa Ribera's appointment to an influential EU commission role encompassing environment and competition, with opponents accusing her of neglecting her duties during the floods.

Regions are in charge of disaster management in Spain's decentralised political system, but the hardest-hit Valencia region's conservative leader Carlos Mazon said he received "insufficient, inaccurate and late" information.

Doubting state agencies was "deeply unfair and deeply dangerous", Ribera told parliament, in a veiled retort to the conservative opposition.

"I would like to thank the work and dedication of the public servants who issued the information as was their duty," she added.

Mazon defended his handling of the catastrophe last week, citing an "information blackout" and criticising a government agency responsible for monitoring river levels.

But Ribera said "there was never an information blackout" and enumerated a lengthy list of warnings issued by public bodies to the regional authorities.

Although the national weather agency issued the highest red alert in the morning of October 29, Valencia residents in many cases only received telephone warnings when water was already gushing through towns.

The socialist-led central government has argued Mazon bore responsibility for the late issuing of the emergency alert.

"Having all the necessary information is of little use if the one who must respond does not know how," Ribera added.

- Political polarisation -

The right-wing opposition Popular Party (PP) has accused the government of abandoning the Valencia region before and after the floods for political gain.

Anger has coursed through Spain over the authorities' perceived mishandling of the country's deadliest floods in decades and the ensuing political polarisation has spilled over at EU level.

The conservative EPP parliamentary group to which the PP belongs refused to approve Spain's nomination for the commission until she reported to the Spanish parliament.

"The European Commission does not deserve to come into existence with a candidate under suspicion," PP leader Alberto Nunez Feijoo wrote on X.

The Socialists and Democrats group have complained that the Spanish right was trying to make Ribera "the scapegoat" for its own failure to manage the floods in Valencia.

By doing so, it was "pushing the entire European Union to the brink in the most irresponsible way", it said.

Socialist Prime Minister Pedro Sanchez on Tuesday said his party always backed PP candidates for the commission and urged "reciprocity" from them.