David Cameron spoke of the: "heartbreaking" sight of flooded farms and homes during an extraordinary day on the Somerset Levels in which Lord Smith, chairman of the Environment Agency, was forced to defy a call to resign from a local MP.
Both men were making their first visit to the Levels more than six weeks since rising waters first began to take their toll, flooding homes, closing roads and wrecking businesses.
Mr Cameron pledged that the Government will do "everything that can be done" to help those affected by the floods and stressed that he has been chairing meetings of the Government's Cobra emergency committee and that the Government has brought in extra pumps, the military and told councils: "If you need to spend money, spend it and central Government will re-imburse".
And in answer to a question from the Western Daily Press on whether financial help will be available for blighted business, he said: "There will need to be a hardship fund."
He met third-generation farmer Tony Davy at Goodings Farm, which is under water in Fordgate.
Mr Davy's 65 cows have been moved off his lands deluged by the floods.
During the visit, Mr Cameron met fire service workers pumping from the property and local MP Ian Liddell-Grainger.
He wore wellington boots to walk around Mr Davy's farm, unlike Environment Secretary Owen Paterson, who was derided for turning up at Northmoor Pumping station 12 days ago in smart black shoes.
He then visited evacuated residents at a private meeting in nearby Bridgwater.
"It's a biblical scene," Mr Cameron, who arrived by helicopter, said as he surveyed knee-deep water surrounding the farm.
"The scale of it here in Somerset is immense when you think of how many square miles are under water". See pictures of the floods from the in our gallery.
"Clearly people here have faced a very tough time and continue to face a tough time and that's why we have got to do everything we can to help.
"So more pumps, we brought in more pumps, more help from the emergency services, more help is there, money to help Somerset get back on its feet, the money is there, the Army coming in to help, whether its helping with sandbags, which they've been doing over the last 24 hours, or looking to see whether temporary bridges can be put in place.
"Everything that can be done will be done and I'll make sure that happens. There are always lessons to learn and I will make sure they are learned but Cobra has been sitting in almost permanent session so we can bring the whole resources of Government, the country, the military to bear.
"But there are lessons to learn. One of the big ones is that the pause in dredging that look place from the late 1990s, that was wrong and we need to get dredging again.
"I've said when the water levels come down and it's safe to dredge, we will be dredging to make sure these rivers can carry a better capacity of water."
He said the community response was "amazing" but warned there are sometimes tougher times when the water recedes and people fully understand the damage.
"We need to make sure that the district councils and Environment Agency and others are working together then and the local MP Ian Liddell-Grainger will do that," he said.
Earlier Mr Liddell-Grainger had launched an astonishing attack on the Environment Agency chief Lord Smith as he prepared to visit the Levels.
Mr Liddell-Grainger called Lord Smith a "coward" and a "git", and even threatened to "stick his head down the loo".
Mr Liddell-Grainger also called on Lord Smith to quit. "I will tell him what I bloody well think of him – he should go, he should walk," he said.
"I'm livid. This little git has never even been on the telephone to me. When I find out where he is, I will give it to him. He's a coward."
Arriving at the Willows and Wetlands Visitor Centre in Stoke St Gregory, Lord Smith dismissed calls for his resignation.
He said he remained "very proud" of the Environment Agency staff.
Residents spoke of their anger at Lord Smith's refusal to apologise for the EA's handling of the crisis and said they were not satisfied at the answers he gave to their questions.
They were furious that he spoke on Monday of there needing to be a choice between flooded front rooms and flooded farmland, a policy which rural communities say has led to the crisis.
Lord Smith insisted the top priority for authorities was "protecting lives", followed by protecting homes and businesses.
He said: "I have no intention of resigning because I'm very proud of the work the Environment Agency and its staff have been doing right round the country in the face of the most extreme weather."
Jim Winkworth, landlord of the King Alfred pub at Burrowbridge, said he was "bloody mad" at Lord Smith's refusal to apologise.
"We thought that's the least he could do," Mr Winkworth.
"He hasn't come down here to apologise, which is what he should be here for. If you apologise it means you're admitting you got it wrong, but he's not fit to do that."