Nigel Farage has been involved in a bizarre clash with rock star philanthropist Bob Geldof on the River Thames.
The Ukip leader was joining trawlers sailing past Parliament in a protest over European Union fishing policies.
But a vessel carrying Geldof pulled alongside Mr Farage's boat and the Boomtown Rats singer unleashed a verbal broadside, calling the Brexit campaigner a "fraud".
Mr Farage was part of a flotilla of around 30 vessels campaigning for a vote to leave the EU in protest at the Common Fisheries Policy.
Around 50 to 60 boats had originally been expected to take part in the protest, passing the House of Commons while David Cameron was answering Prime Minister's Questions.
Geldof and his Remain supporters blasted out the song In With The In Crowd from a large on-board sound system as they pulled alongside.
Addressing Mr Farage over a PA system on his vessel, the Sarpedon, Geldof said: "You are no fisherman's friend."
He said that while Mr Farage was on the European Parliament fisheries committee he attended just one out of 43 meetings.
"You are a fraud, Nigel. Go back down the river because you are up one without a canoe or a paddle.
"Stop lying. This election is too important."
Speaking to reporters accompanying him on the Thames, Mr Farage branded the Geldof protest "just disgusting".
He said: "These are communities that have been devastated. These are communities that no-one has listened to for years.
"They are here today, they have taken - some of them - several days out of their working week to come and make their protest, to say Look, we want to take back control of our seas, we want to get jobs back in this industry'.
"To see multi-millionaires frankly mocking them is a pretty shameful sight."
Mr Farage said the protest was taking place eight days ahead of the June 23 referendum because EU membership had "destroyed our industry".
"The governing principle of the common fisheries policy is that of 'equal access to a common resource'," he said.
"Fish stock that should be within the UK's internationally-recognised territorial waters is now shared with our European partners. This has led to a 60% drop in oversized landings and the loss of tens of thousands of jobs in our industry."
Jobs were also being lost in the charter angling fleet because of new EU regulations on recreational sea angling, said the Ukip leader, who added that Norway, outside the EU, was able to control stocks up to 200 miles off its shores and had a "booming" commercial fishing and angling industry.
"EU membership has destroyed our industry," said Mr Farage.
"Today's flotilla is not a celebration or a party but a full-throttled protest. We want our waters back."
Greenpeace UK executive director John Sauven said: "When Nigel Farage had a chance to stand up for UK fishermen in Brussels, he bunked off. His no-show voting record proves he's no fisherman's friend but a cynical opportunist exploiting the harsh predicament of many fishermen for political gain.
"What's threatening the livelihoods of thousands of sustainable, family-run businesses is the grossly unfair division of fish quota overseen by successive UK governments. The root of the problem lies in London, not Brussels.
"Quitting the EU will only condemn the industry to years of wrangling over new fisheries agreements, with no guarantee of a better deal for fishers or stronger protections for our seas."
Geldof said in a statement: "The In Crowd are here to say to Farage's fishy flotilla: 'Don't sink Britain'.
"Look at the facts: Farage is no fisherman's friend. Farage had the chance to help fisherman in the EU, but only attended one out of 43 fisheries committee meetings.
"The UK gets the second biggest quota out of member states and has the biggest profit of any EU member state. Leaving Europe would be disastrous for our country, our economy, our public services and our fishing industry."
The Ukip leader hinted that he could quit politics if Brexit happens.
"I might go and get a real job, you never know," he said. "I haven't thought about it. Everything in my career in politics has been about next Thursday, everything."
Police vessels and the harbour master were in attendance as Geldof's vessel and the Fishing for Leave flotilla circled on the river outside the Houses of Parliament.
Speaking to the Press Association, Mr Farage said: "The Common Fisheries Policy works on the principle of equal access to the common resource. What that means is that we have to share the fish in our waters with the rest of the European Union.
"Sensible countries like Norway, the Faroes and Iceland do no such thing. These industries, these communities have been devastated now for decades and they have come here today to be heard."
He added that Geldof was "deeply ignorant about how the Common Fisheries Policy works" and "it ill befits multi-millionaires coming to drown out ordinary men and women from the fishing industry who have come to have a fair say".
Mr Farage said: "We used to protest against the establishment and now the establishment protests against us. We must be getting something right."
The Ukip leader said there had been a "shift" in voters' opinions and Leave "have had some momentum".
"But there's still eight days to go, eight days is a hell of a long time, it's all to play for," he said.
"I'm sure the Remain campaign will promise us poverty, starvation perhaps, plagues of black locusts.
"I want to hear the Prime Minsiter tell me why the EU is a good thing, why he loves the flag. I want him to tell me he stands to attention when he hears the anthem, he is welcoming a European army and, as he has since 2005, Turkey as a member by 2025.
"Let's hear an honest argument from the Prime Minister and the Chancellor as to what's good about the EU, not an endless series of negative empty threats."
David Cameron said the UK fishing industry had grown by around 20% thanks to Government reforms, and insisted it would be hit with tariffs on the sale of fish if Britain pulled out of the EU.
At Prime Minister's Questions, he said: "We export every year about a billion pounds worth of fish to the EU, and there is no country in the world that has a trade agreement with the EU that doesn't involve tariffs, taxes, on the sale of its fish,so there's no way we would get a better deal from the outside than the deal we get on the inside."
Mr Cameron spoke after Jeremy Corbyn criticised the Government for giving the majority of its fishing quota to large companies, urging people to "stop blaming Brussels".
The Labour leader said: "You will be very well aware that reforms that were made three years ago actually put the power back into the hands of member states and it's the UK Government that has given nearly two-thirds of the English and Welsh fishing quotas to just three companies.
"Thus excluding small fishing communities all along our coasts.
"Can you stop blaming Brussels on this and tell us small-scale and sustainable fishing communities what action you will take to allow them to continue their work and indeed go further out in collecting fish?"
The stars of Channel 4's The Last Leg pulled alongside, with comedian Josh Widdicombe shouting questions to Mr Farage.
In the impromptu interview, Widdicombe joked: "Are you in or out, Nigel? Pick a side. Finally commit."