London politicians have called for unity as Britain leaves the European Union.
The UK has quit the bloc almost a year after it was originally due to leave.
The country will now enter a transition period, running until the end of the year, maintaining the status quo on travel, freedom of movement, and trade with Europe.
The government will now try to negotiate a new trading relationship with the EU, which would take effect in January 2021.
But there will be changes after today – British MEPs will lose their seats in the European parliament, the UK will stop attending EU summits, and passports will revert from red to blue.
Brexit Day is a significant step towards delivering the result of the 2016 referendum, which saw 52% of Brits – more than 17million people – vote to leave.
But Londoners bucked the national trend on Europe, with 60% of voters in the capital opting to remain.
Today, Mayor of London Sadiq Khan said the capital “remains a truly global, European city”.
Mr Khan has been a vocal opponent of Brexit since the referendum.
He said: “London continues to be a beacon for progressive ideas, for liberal values and for decency and diversity.
“And we will continue to welcome people from around the world, regardless of the colour of their skin, the colour of their passport or the colours of their national flag.
“At a time of continuing uncertainty, I want to send a particular message to the more than one million Europeans who have decided to make our city their home: you are Londoners.”
Conservative mayoral candidate Shaun Bailey – who supports Brexit – said this marks “the end of a saga for the country”.
He said: “What’s been really bad about the discourse around Brexit is people have used it to wedge communities apart.”
“If you voted to leave or stay, we’re leaving now – so let’s forge forward and see what we can do.
He added: “We’re not leaving Europe, we’re leaving the European Union. We’ll always be European.
“Geography has given us that, history has given us that – but this is about moving forward and what we can do being British.”
Independent mayoral candidate Rory Stewart – who was booted off the Conservative benches in Parliament for voting to block a no-deal Brexit – said it is now “time to move forward, and stop focusing on the battles of the past”.
Mr Stewart said the Mayor of London must be pragmatic, focus on promoting London’s interests, and ensure “the greatest city in the world” continues to prosper after Brexit.
And Liberal Democrat Siobhan Benita – who joined the party the day after the EU referendum – said Brexit Day was a “poignant” moment.
She said: “Like so many people I campaigned hard to stay in the European Union, so on a personal level it’s not a day that I wanted to see.
“But as a candidate for Mayor of London I’m now entirely focused on making sure that London retains that global position as the city of choice for businesses, for investors, for tourists.
“There is so much potential here – London is a really brilliant, resilient city full of potential, and we now have to seize all those opportunities.”
Green candidate Sian Berry agreed that for both Leave and Remain voters, today is “hugely significant”.
She said: “Where we go from here will say everything about us.
“No we won’t be part of the EU. But the need to work across countries, to build solutions together to stop runaway climate chaos, to protect workers’ rights and to make sure that we don’t lose precious freedom of movement – that remains unchanged.”