Much of Venice was under water on Wednesday night after the highest tide in 50 years ripped through the historic Italian city, beaching gondolas, trashing hotels and sending tourists fleeing through rapidly rising waters.
The government in Rome was expected to declare a state of emergency at a cabinet meeting on Thursday after Prime Minister Giuseppe Conte described the flooding as "a blow to the heart of our country".
Officials blamed climate change while shopkeepers on the Grand Canal raged against those who have failed to protect the UNESCO city from the high tide.
They said corruption had repeatedly delayed a barrier protection system that could have prevented the disaster.
"The city is on its knees," Venice mayor Luigi Brugnaro said in an interview with national broadcaster RAI.
"There's widespread devastation," he said in the famed St Mark's Square, which bore the brunt of the flooding.
"In all likelihood the damage from last night runs into hundreds of millions of euros."
"It hurts to see the city so damaged, its artistic heritage threatened."
"These are the effects of climate change."
"The future of Venice is at stake," he warned. "We cannot live like this anymore."
"Global warming will destroy our planet if we do not immediately reverse the direction."