With the latest polls covering the UK’s referendum on European Union membership reflecting a neck and neck leave-versus-remain split, the satirist used his HBO bully pulpit Sunday to agitate against the opt-out—lest Britain face dire consequences.

“I know,” said Oliver, a native of Birmingham, England. “If you’re watching this outside the UK, you’re probably thinking, ‘Why should I care what England does about the EU? Honestly, as long as those crooked-tooth scone goblins keep shooting out royal babies and episodes of Dr. Who, I don’t give a tally-ho fuck what happens there.’”

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“Fair enough,” he continued. “But a Brexit, or British exit, could have wide ranging implications both for the UK and the world’s economy.”

‘Brexit’ arguments are “b—s—!”

After presenting a brief primer on the European Union’s 71-year-old politico-economic union, the Last Week Tonight host acknowledged the EU’s myriad imperfections: “It’s large, confounding and relentlessly bureaucratic,” he said. “Think of it like Gerard Depardieu. It’s an unwieldy European body that’s a source of great bewilderment.”

But Oliver dismissed pro-Brexit arguments as “bullshit” and proceeded to dismantle the Leave camp’s primary reasoning. Former London mayor Boris Johnson, one of the leading #VoteLeave advocates, has claimed the UK sends £350 million a week to the EU. “That number has been thoroughly debunked. It’s actually about £190 million pounds a week when you consider a rebate the UK receives and other money the EU has to send back,” said Oliver, adding: “If Britain does leave the EU, may have to spend that much to access the common market.”

He also brushed aside complaints about the European Union’s onerous regulations, showcasing a zany poem by an Austrian politician to underscore how influential global powers including President Obama, China, Japan, India and the EU itself are backing #VoteRemain.

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“The Brexit is, to put it simple, not like an ordinary pimple,” said Eugen Freund, MEP, Austria in a clip shown on Last Week Tonight. “You take some cream, you put it on, a few days later it is gone. It is a complicated matter. More like a novel, not like a letter. To understand the story well, you’ve got to listen. I will tell you what will happen. So sit back and let me rappen.”

“I mean, come on Britain!” exclaimed Oliver. “If a middle-aged Austrian diplomat spitting dope half rhymes in a busy hallway—if he doesn’t win you over, nobody will!”

What’s more, Oliver said, the British Treasury, the Bank of England, the International Monetary Fund, the National Institute of Economic and Social Research, PriceWaterhouseCoopers, Oxford Economics and the Centre for Economic Performance all have predicted that a Leave vote will negatively effect Britain’s GDP.

“If leaving is so universally seen as a bad idea, then who the fuck is in favor of it?” exclaimed Oliver, then going to explain that the leading group backing Brexit is the UK Independence Party (UKIP), an ultra-conservative group with hard-line anti-immigration views.

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UKIP argues Brexit would enable the UK to “significantly reduce racism, preventing both EU citizens from taking UK jobs and non EU citizens from sneaking in to commit terrorism attacks,” he continued. “It is hard for me to overstate to you how poisonous things have become in England. Just this week, MP Jo Cox was killed in the street. And the man charged for it gave his name in court as ‘Death to traitors, freedom for Britain.’ And in that cauldron, people are being asked to make a major political decision. And incidentally, regarding immigration, even if you believe that tightening borders is what Britain needs to do, you should know that opting out of the EU will not necessarily enable Britain to do that.”

“To recap: immigration policy may not change, hysteria over regulation is a red herring, the cost of membership are reasonable, and the economic benefits of staying appear to outweigh the cost, and yet, polls suggest my homeland is on the edge of doing something absolutely insane,” said Oliver.

‘Absolutely crazy’

He went on to assail the “hypothetical” policies that would cut Britain off from the rest of Europe (and end immigration) by pointing out such regulations would also effectively eliminate free trade with the continent. “If Britain wants a good trade deal with the EU, it’s probably going to have to abide by most of its rules,” noted Oliver.

In closing, however, the host displayed a spirit of generosity toward the Leave camp and acknowledged the “innate British desire to tell Europe to go fuck itself.” He described the EU as a complicated, bureaucratic, ambitious, over-bearing, inspirational and consistently irritating institution “that Britain would be absolutely crazy to leave.” And Oliver presented a song that both “relentlessly insults Europe and quietly acknowledges how lost we’d be without it”:

“Fuck you Eur-o-pean Union, Tally-ho, you fucking pricks!

We are the United Kingdom, you can eat our spotted dicks!

That being said, we’re not going to leave you/

Turns out we need you nonetheless/

Fuck you European Union/

It feels good to tell you this!”

Watch the entire segment below:

Chris Lee is a former staff writer for Entertainment Weekly, The Los Angeles Times, Newsweek and The Daily Beast. He covers entertainment, culture and business in Los Angeles.