Members of the European Parliament approved the terms of the U.K.’s departure from the European Union today, paving the way for the country to leave the bloc on Friday.

E.U. lawmakers ratified the Brexit Withdrawal Agreement by 621 votes to 49.

The U.K. is due to leave the bloc, which it joined in 1973, at 23:00 GMT on Friday.

A transition period running until the end of the year will now take effect, during which trade negotiations between the E.U. and the U.K. will be finalised.

That timetable is viewed as ambitious by many observers of trade discussions, which can often take years to agree.

During this period, the U.K. will remain within the E.U.’s economic bloc although it won’t have a say in policy.

The President of the European Commission, Ursula von der Leyen, said ratification of the withdrawal deal was “only a first step” towards a new partnership between the EU and the UK.

“We are considering a zero-tariff, zero-quotas free trade agreement. But the precondition is that E.U. and British businesses continue to compete on a level playing field. We will certainly not expose our companies to unfair competition,” von der Leyen added.

The ratification comes more than three years since the U.K. voted in a referendum to leave the E.U., delayed by long arguments within the U.K. Parliament about whether and how the country should depart.

The issue was settled in December with the election by a large majority of Eurosceptic Prime Minister Boris Johnson.