"The reality is that today I am the focus of criticism, noise, hatred, and tension," Carlos Mazon said in a televised address, adding: "I can't go on anymore."

Mazon has faced fierce scrutiny over his handling of the October 29, 2024 catastrophe that killed more than 230 people, but has consistently rebuffed calls for his resignation.

Last week, relatives of the victims shouted "murderer", "coward" and "get out" at Mazon as he arrived for a state memorial service for the victims in the Mediterranean city of Valencia.

Mazon's regional administration -- primarily responsible for the emergency response under Spain's decentralised system -- sent alerts to residents' mobile phones when flooding had already started in some places.

The alert also came more than 12 hours after the national weather agency had issued its highest alert level for torrential rains.

Despite signs of severe flooding, Mazon did not change his schedule, going ahead with a lengthy lunch with a journalist and appearing in photos tweeted by his staff receiving a sustainable tourism certification.

"I should have had the political vision to cancel my appointments and visit" the affected areas on the day of the disaster, Mazon said Monday.

"I know I made mistakes. I acknowledge them and I will live with them all my life," he added.

"I have asked for forgiveness, and today I repeat it again. But none of them were due to political calculation or bad faith."

- Regular protests -

Mazon, a member of the conservative Popular Party (PP) that sits in opposition to the Socialist-led national government, has argued his administration did not have the information needed to warn people sooner.

Campaigners have staged regular demonstrations against Mazon, often on or near the monthly anniversaries of the disaster.

More than 50,000 people, many carrying photos of family members who died in the floods, took to the streets of Valencia city in the latest such protest on October 25 to demand that Mazon resign.

Residents told Spanish media that by the time they received the mobile alert, muddy water was already surrounding their cars, submerging streets and pouring into their homes.

In a poll published last month in El Pais newspaper, 71 percent of Valencia residents said Mazon should resign.

The floods hit 78 municipalities, mostly in the southern outskirts of the city of Valencia, sweeping away 130,000 vehicles, damaging thousands of homes and generating 800,000 tonnes of debris.