IT was a “fantastic moment,” Boris Johnson declared as he formally signed the Withdrawal Agreement that next Friday at 11pm will usher in a new era as Britain leaves the European Union.

Sitting in the anteroom to the Cabinet Room, the Prime Minister used a Parker fountain pen, which, No 10 helpfully pointed out, was “traditional for ceremonial signings in Downing Street”.

After putting pen to paper, Mr Johnson said: “The signing of the Withdrawal Agreement is a fantastic moment, which finally delivers the result of the 2016 referendum and brings to an end far too many years of argument and division.

“We can now move forward as one country with a Government focused upon delivering better public services, greater opportunity and unleashing the potential of every corner of our brilliant United Kingdom, while building a strong new relationship with the EU as friends and sovereign equals.”

The signing was witnessed by EU and Foreign Office officials who transported the treaty from Brussels, where it was earlier signed by Charles Michel and Ursula von der Leyen, the respective Presidents of the European Council and Commission.

Mr Johnson’s signature was witnessed by No 10 staff including David Frost, the PM’s Chief Negotiator.

Earlier, Downing St revealed the original Withdrawal Agreement would be kept in the EU's Brussels archive with the UK getting a photocopy. This, it said, was per the agreement.

On Wednesday, the European Parliament is expected to vote to approve the UK-EU deal, paving the way for Brexit Day.