Britain left the European Union on Friday, ending more than four decades of economic, political and legal integration with its closest neighbours.

But things will feel the same for many months, owing to a transition period intended to allow both sides time to agree the terms of their future partnership. 

Three Brexit deadlines came and went before the British parliament finally ratified the divorce agreement.

Britain left the European Union 43 months after the country voted for Brexit in a June 2016 referendum.

Nothing will change for most people in Britain thanks to the transition period, which preserves the status quo until at least December 31, 2020.

But Britain will lose its representation and voting rights in the EU institutions. This includes having no British members of the European Parliament.

Here are the key moments ahead:

February/March: trade talks begin

Britain says it is ready to start trade talks on February 1, but EU members states are still discussing what they want from the negotiations.

British Prime Minister Boris Johnson is to flesh out his ideas for a free trade agreement along the lines of a recent EU deal with Canada, in a speech in early February.

The EU mandate could be approved by national ministers on February 25, officials in Brussels suggest, which would mean talks could begin around March 1.

Britain is hoping to open trade talks with the United States and other non-EU countries around the same time.

Trade is not the only issue that must be resolved with Brussels, however. Britain and the EU closely cooperate on security and law enforcement, education and energy among many other issues.

July 1: extension deadline

The transition period is scheduled to last until December 31, 2020.

Britain can ask to extend this for one or two years, but must inform the EU of its request by July 1. 

Johnson insists he will not do this, saying that Britain must be free of EU rules and regulations as soon as possible.

December 31: transition ends

Without an extension or a trade agreement, relations between Britain and the EU will be severed at the end of 2020.

A new deal would allow the two sides to embark on a new partnership.

Failure to agree would see cross-Channel trade, transportation and a multitude of other ties severely disrupted overnight.