British and EU trade negotiators embarked on high-stakes talks aimed at forging a new post-Brexit relationship on Monday, with timing tight and the sides far apart on key issues.

The EU's chief negotiator Michel Barnier and his UK counterpart David Frost met in Brussels, launching several months of intense talks involving around 100 officials on each side.

Barnier, in an uncharacteristic display of podium-thumping, has told Britain to fully respect the binding Brexit withdrawal treaty
Barnier, in an uncharacteristic display of podium-thumping, has told Britain to fully respect the binding Brexit withdrawal treaty AFP / Kenzo TRIBOUILLARD

The negotiations began just over a month after Britain left the EU, and are meant to wrap up by the end of this year -- an exceedingly tight timeframe that few see as feasible for anything but a bare-bones accord.

The deadline is effectively December 31, the end of the UK's current transition period during which it trades like an EU member with no tariffs or other barriers.

The UK's current transition period ends on December 31 and British Prime Minister Boris Johnson has ruled out extending it
The UK's current transition period ends on December 31 and British Prime Minister Boris Johnson has ruled out extending it POOL / Tim CLARKE

British Prime Minister Boris Johnson has ruled out extending the transition and both sides are looking to an EU-UK summit in June to decide whether talks are worth continuing.

The negotiations have been clouded by mistrust and weeks of chest-beating as each side has accused the other of reneging on high-ambition goals set out in a political declaration struck last year.

Britain will issue blue passports in March for the first time in almost three decades following its departure from the EU
Britain will issue blue passports in March for the first time in almost three decades following its departure from the EU UK HOME OFFICE / STRINGER

This week's talks in Brussels will end on Thursday, after two days in which the teams will divide to cover 11 key topics for the future relationship. The next round will take place in London, and thereafter alternate between the two capitals.

Mandates published last week highlighted the EU's aim of securing a "level playing field" to prevent Britain from undercutting European standards on labour, tax, environment and state subsidies.

Meanwhile the UK is insisting on setting its own rules in the name of "economic and political independence".

Fishing, of relatively minor economic importance but of totemic significance to Britain and EU states such as France and Spain, could be the flashpoint that scuppers a deal
Fishing, of relatively minor economic importance but of totemic significance to Britain and EU states such as France and Spain, could be the flashpoint that scuppers a deal AFP / William EDWARDS

The acrimony pushed the British pound 1.3 percent lower against the euro on Monday amid fears that Britain's hard-line stance would hurt the economy.

Key Brexit points as London and Brussels negotiate new arrangements, including a trade deal, to guide future relations.
Key Brexit points as London and Brussels negotiate new arrangements, including a trade deal, to guide future relations. AFP / Gal ROMA

Experts warned that the two sides are on a collision course, with a deal highly unlikely without concessions.

British Brexit negotiator David Frost and UK ambassador Tim Farrow came to the EU's headquarters for the first round of talks that will be split between London and Brussels
British Brexit negotiator David Frost and UK ambassador Tim Farrow came to the EU's headquarters for the first round of talks that will be split between London and Brussels AFP / Kenzo TRIBOUILLARD

"A deal between the EU and the UK by the end of the year is still possible, but it will require both parties to drift away from their opening positions," said Sam Lowe, a senior research fellow at the Centre for European Reform.

"In practice, it requires the UK to move a lot, and the EU to move a little," he said.

Underlining tensions, Barnier, in an uncharacteristic display of podium-thumping, has warned Britain that any backsliding on its EU divorce terms would torpedo trade talks.

The Brexit deal notably requires checks on British goods crossing the Irish Sea into the UK territory of Northern Ireland that Johnson now says are unnecessary.

"Clearly, at the beginning of any negotiation, there's a bit of posturing. Both sides want to state the strongest possible case," said Fabian Zuleeg, head of the European Policy Centre.

Experts see a deal limited to goods as the most likely outcome, but that would still require customs checks for products crossing the Channel and lacks the ambition called for by businesses.

But fishing -- of relatively minor economic importance but of totemic significance to Britain and EU states such as France and Spain -- could be the flashpoint that scuppers a deal.

Barnier has emphasised that fishing is "inextricably" linked to the whole agreement. The EU is demanding that its fishing boats continue to have access to British waters in return for British fishermen being able to sell their catches to their biggest and closest market.

If there is no broad trade deal, economic pain will be felt on both sides -- but especially in Britain and in Ireland, the EU member most dependent on trade with the UK.

Without a deal, UN economists calculate the UK would lose export revenues of up to 29 billion euros ($32 billion) a year. The EU buys nearly half of all British exports.

"At the end we will see if it's possible to have a balanced agreement," said Didier Reynders, the EU commissioner from Belgium, whose country trades heavily with Britain.

"Of course, we are in favour of a real positive agreement for both... If it's not possible we will be ready to organise something else," he told France 24.

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