The presidents of the EU's three major institutions have heralded Brexit Day by expressing hope for continued strong ties with Britain but with warnings for the country over the consequences of the split.

In a joint letter published in several newspapers across the continent, European Commission president Ursula von der Leyen, European Council leader Charles Michel and European Parliament president David Sassoli said the three bodies would do all in their power to make the EU's future partnership with Britain a success.

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They issued a reminder that the closeness of that partnership would hinge on decisions to be taken in the 11-month transitional period, "because every choice has a consequence".

"Without the free movement of people, there can be no free movement of capital, goods and services," they wrote.

"Without a level playing field on environment, labour, taxation and state aid, there cannot be the highest quality access to the single market.

"Without being a member, you cannot retain the benefits of membership."

The three presidents said they had "always deeply regretted" the UK's decision to leave, and that they shared a fondness for the UK "which goes far beyond membership of our union".

Prime Minister Boris Johnson will hail the "dawn of a new era" as the UK leaves the European Union.

At 11pm on Friday, bonds dating back to 1973 when the UK joined the European Economic Community will be broken, but the Prime Minister insists Brexit marks "not an end but a beginning".

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Very little will change at the moment of Brexit as a result of the deal which Mr Johnson agreed with Brussels and the 27 remaining member states.

The UK faces further uncertainty as both sides seek to strike a trade deal by the end of the year.

In a symbolic move, Mr Johnson will chair a meeting of his Cabinet in Sunderland, the city which was the first to back Brexit when results were announced after the 2016 referendum.

In what Number 10 billed as an "address to the nation" released an hour before the moment the UK leaves the EU, Mr Johnson will attempt to sound an optimistic note about the future and promise to heal the divides which have been caused in the bitter Brexit battles.

He will say: "Our job as the government - my job - is to bring this country together and take us forward."

He will call Brexit "the moment when the dawn breaks and the curtain goes up on a new act".

Mike Russell has said the Scottish Government will look to ensure the UK stays closely aligned with the EU so Scotland can rejoin if it becomes independent.

Scotland's Brexit secretary made the comment shortly before the First Minister set out her "next steps" for the country's constitutional future and on the same day the UK officially leaves the EU.

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Speaking on the BBC's Good Morning Scotland, Mr Russell claimed the only way for Scotland to re-enter the bloc would be to become an independent nation and that he would "positively" make the case for close alignment to EU rules.

He said: "One of the issues is to make sure that we stay as close as we can to European regulation and rules.
"That will be part of our concerns and we'll be doing that positively."

Mr Russell pointed specifically to the prospect of selling fish into the EU post-Brexit, saying regulations would have to be "aligned" to ensure Scottish fishermen would be able to trade with the bloc.

Supporters of leaving the EU say the UK economy will have an upturn following the end of the transition period in December but Mr Russell dismissed that claim.