The battle over whether or not Britain should stay in the European Union spilled from the airwaves to the River Thames on Wednesday.

In one of the more surreal moments in the campaign for the June 23 referendum, fishermen who had organized a flotilla on the London river to protest EU fishing policies shot off water hoses at dinghies full of rival campaigners, who crashed the fishermen's flotilla as it traveled up the Thames to the Houses of Parliament.

As if that weren't enough, rock star philanthropist Bob Geldof sidled up to the boat carrying noted "leave" campaigner Nigel Farage and told him he was up the river without a paddle.

"You are no fisherman's friend," Geldof said.

The incidents — described by police as good natured — underscore how complex the campaign has become as Britain prepares to go to the polls on June 23. The reach of the EU into every aspect of life has meant that all sorts of groups — from scientists to CEOs — have registered an opinion on whether to stay or go.

Rolls Royce became the latest big business to register a view, arguing that Britain should stay in a letter to its 23,000 employees in the U.K. The engineering company warned that a British exit, or Brexit, would be bad for business amid uncertainty about the future.

Britain's Treasury chief sounded another warning about how a vote to leave the EU would damage the economy, arguing he would have no choice but to raise taxes and slash spending.

Osborne's remarks on the BBC seized attention in part because of their dire nature. He said that the government would have to raise income and inheritance taxes to fill a 30 billion pound ($42.4 billion) budget "black hole" that government ministers say will emerge if Britain leaves the EU.

"No Conservative wants to raise taxes — least of all me," Osborne said. "But, equally, Conservatives understand — and, indeed, I suspect many Labour politicians understand — that you cannot have chaos in your public finances."

Furious members of his party backing Britain's exit say they'll block any attempts to impose an emergency "punishment" budget and warned that Osborne's position would be "untenable" if he tries to push through tax increases. The opposition Labour Party, which backs "remain," also warned they would not support any budget that slashed public services.

Just to rub it in, some 57 Conservatives signed a letter laying out their displeasure in a back and forth that underscores the political civil war among the Tories over the issue.

"If he were to proceed with these proposals, the chancellor's position would become untenable," they said. "This is a blatant attempt to talk down the market and the country."

As lawmakers challenged Prime Minister David Cameron to explain his views to the House of Commons on Wednesday, the flotilla of some 30 vessels taking part in the "leave" campaign glided up the Thames outside.

Joining them on their journey were a smaller number of vessels with flags backing the "remain" camp. Reflecting the level of the debate, one of the "leave" trawlers turned a water hose on two of the "remain" dinghies. It was not enough to hurt anyone but left the occupants sodden.

There were also water-infused exchanges of views between Geldof and Farage.

Farage branded the Geldof protest "just disgusting," and called him "deeply ignorant about how the Common Fisheries Policy works."

The policy is a set of rules for managing fishing fleets and stocks — and like all things in this debate, it is controversial.

It was created to manage a common resource: fish stocks, putting limits on catches. Experts say stocks have been overfished for decades — if not longer — and there is concern that without intervention, some species will never recover.

The goal of the policy is to give equal access to EU waters and fishing grounds, allowing for fair competition. But its efficiency has been questioned and some fishermen complain that it has been neither fair nor equitable.

"I think everyone knows it has to be done," said Bryce Beukers-Stewart, a fisheries biologist expert from the University of York. "But not everyone is happy in the way it is being done."

As Britain is an island, the issue of whether the policy is fair is a deeply emotive one. Entire communities have been decimated by declining fish stocks and blame the policy.

Prime Minister David Cameron argues that under his government, fishing has grown by 20 percent thanks to reforms. But Labour leader Jeremy Corbyn says the problem is the government's decision to give the majority of its quota to large companies. He urged people to "stop blaming Brussels."

The arguments over who is to blame did not interrupt Farage in any way. He argued EU membership had "destroyed our industry."

"We want our waters back," he said.