BRITAIN and Brussels are on collision course for a post-Brexit tug-of-war after Boris Johnson and Michel Barnier set out sharply competing visions of a future trade relationship.

Just three days after Britain formally left the EU, the Prime Minister, in the grand baroque splendour of the Painted Hall at the Old Royal Naval College in Greenwich, set out his vision of Britain becoming a global champion of free trade.

He told his high-flown audience of ambassadors and influential business leaders that the UK had “no need” to abide by the rules of the body it had just left.

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"There is no need for a free trade agreement to involve accepting EU rules on competition policies, subsidies, social protection, the environment or anything similar, any more than the EU should be obliged to accept UK rules," declared Mr Johnson.

"The UK will maintain the highest standards in these areas; better in many respects than those of the EU without the compulsion of a treaty," he said.

And the PM confirmed Britain faced a binary choice; if a Canada-style agreement were not possible, the he would be prepared to walk away without a full trade deal like Australia's relationship with the EU. Either way, he had no doubt the UK would “prosper mightily”.

But across the English Channel, Michel Barnier was setting out a different vision of life after Brexit between Britain and the EU.

The EU’s Chief Negotiator laid out the battles ahead from access to UK fishing waters to the application of a "level playing field" on issues including state subsidies, environmental standards and workers' rights.

Mr Barnier upped the ante on the iconic subject of fishing, insisting that allowing European trawlers into British waters was "inextricably linked" to securing a trade deal.

He also made clear the EU would insist on the European Court of Justice continuing to play a role in certain respects; a move totally rejected by the Government.

The EU’s draft strategy for future trade talks, not due to begin until next month, urged Britain to continue to “ensure the application” of EU state-aid rules and to remain aligned with EU environmental and labour market rules.

In return, Brussels would offer the UK a “highly ambitious” trade deal, which would include tariff-free, quota-free trade in goods, as well as one covering services.

And the EU Chief Negotiator pointed to the joint Political Declaration, agreed with Mr Johnson, which committed the UK to "robust commitments to ensure a level playing field". No 10 later described a level playing field as an “EU concept; it’s not a generally accepted one”.

On fishing, the PM said while the Government was ready to consider an agreement with Brussels, he stressed "it must reflect the fact that the UK will be an independent coastal state from the end of this year, controlling our own waters".

He noted: "Under such an agreement there would be annual negotiations with the EU, using the latest scientific data, ensuring British fishing grounds are first and foremost for British boats."

Shortly before Mr Johnson spoke, the EU set out its draft negotiating mandate, calling for "reciprocal access" for fishing vessels, and stating that a free trade area with no tariffs or quotas was contingent on a "level playing field ... ensured through robust commitments".

Mr Barnier told reporters in Brussels: "It's clear that the agreement that we wish to have in the interests of UK fishermen and in the interests of European fishermen - I call that reciprocal access to our territorial waters and our markets - that agreement on fisheries will be inextricably linked to the trade agreement, as indeed will be... the agreement on the level playing field agreed with Boris Johnson."

However, he declared that "where there's a will, there's a way" to reach a deal.

"But we are constrained by the decision, if it's confirmed, the decision of Boris Johnson to leave the single market and the customs union at the end of this year," explained Mr Barnier.

The EU chief negotiator pointed out he had a "very direct and frank relationship" with the PM but then argued completing the whole trade deal within 11 months, as Mr Johnson envisages, would be impossible.

In response to the PM’s vision of and independent Britain doing simultaneous trade talks, Stewart Hosie for the SNP said: “The reality of Boris Johnson’s rhetoric is that diverging from high EU standards would only rollback on protections in place on workers’ rights, environmental standards, food safety, and regulations to protect our diverse and vital sectors.

“After only a matter of days of formally leaving the EU and entering into the transition period, the Tory Government has already signalled its intention to pursue a race to the bottom trade deal that will leave us all poorer and worse off.”

The party’s trade spokesman argued that shifting away from EU standards and keeping the threat of a no-deal exit on the table would be an act of “economic self-harm,” that would cost thousands of jobs, harm businesses, and hit people’s livelihoods.

“People will not be fooled by the Tory Government's attempt to talk up a so-called ‘Australian-style’ deal; given Australia does not have a free trade agreement with the EU and trades on WTO terms with tariffs.

"The UK Government must commit to prioritising its future trading relationship with the EU - the UK's closest trading partner - ahead of the Brexit bluff and bluster of global trade deals.

“It’s clearer than ever that the people of Scotland must have a choice over their future as an independent country, rather than the Brexit Britain being imposed upon us against our will,” added the Dundee MP.

Ed Davey for the Liberal Democrats was equally critical, saying: “Paying lip-service to free trade after taking us out of the largest free trade zone in the world is nothing short of hypocrisy.

“All it shows is that Johnson is happy to jeopardise our trade with the EU for political gain. Refusing to practically commit to a level playing field is simply not a serious negotiating strategy.”

Sir Ed added: “Boris is gearing up for no-deal masqueraded as an Australian-style agreement, that will hollow out our trade. The Liberal Democrats will continue to oppose his dangerous plans and fight to maintain our most important trading relationship."