The UK and European Union will remain “allies, partners and friends”, the Government said as both sides geared up for potentially fractious trade talks.

Europe minister Christopher Pincher, representing the Government at the last scheduled ministerial meeting during the UK’s membership of the EU in Brussels, said it would be a “historic week”.

While the UK will leave the EU at 11pm on Friday, the negotiations on trade and other aspects of the future relationship with Brussels which will follow already look set to be difficult.

Mr Pincher, attending the general affairs council, said: “I’m here to reassert to my EU friends and colleagues that, though we are leaving the EU, we are not leaving Europe.

“Our shared history, our shared values, our commitment to security and prosperity continue as equals – sovereign equals.”

Mr Pincher said he would deliver the message that “as we leave the EU we will always be allies, partners and friends”.

In a sign of the choppy waters ahead, Brussels is set to insist European judges continue to hold sway in Britain after Brexit – something that will be strongly resisted by Brexiteers.

According to the Times, a leaked diplomatic document suggests the EU is preparing to demand that the European Court of Justice (ECJ) is able to enforce rules on trade, fishing and security even after Britain is classified as a third country.

A document seen by the paper reportedly states that having a defined role for the Luxembourg court, which adjudicates on EU laws, would “ensure consistent interpretation of the agreement” between the UK and EU.

The EU’s chief negotiator, Michel Barnier, said the UK’s insistence on moving away from Brussels-made laws and the scrutiny of its judges meant trade without some form of customs checks was “impossible”.

Speaking in Belfast on Monday, he said: “The UK has chosen to become a third country, to leave the single market and the customs union, to leave behind the EU’s framework of common rules, common supervision and common Court of Justice.

“It has chosen to create two regulatory spaces. This makes frictionless trade impossible. It makes checks indispensable.”

In further comments that could worry Brexiteers, Irish premier Leo Varadkar also indicated that Brussels would look for concessions on fishing in exchange for the UK’s financial services industry to have better access to the European single market.

The Taoiseach told the BBC: “What happens in these things is trade-offs.

“You may have to make concessions in areas like fishing in order to get concessions from us in areas like financial services.”

Responding to the comments, Prime Minister Boris Johnson’s official spokesman said: “We are going to be taking control of our fishing waters. We have been clear on that.”