Economic progress and jobs in the capital could be under “serious” threat in the event of a no-deal Brexit, the Mayor of London warned.

Mayor of London Sadiq Khan has said leaving the European Single Market could slow down economic growth in the capital – resulting in tens of thousands of fewer jobs.

Mr Khan also believes that even if an arrangement is made for the UK to remain in the Customs Union after Brexit, the country’s competitiveness will still be permanently damaged without access to the Single Market.

He said: “London remains the UK’s economic powerhouse and one of the world’s most dynamic cities – and whatever happens with Britain’s departure from the European Union, that will always be the case.

“I’m proud of the progress that has been made.

“Over the last two and half years a number of key indicators show that the capital continues to make progress thanks to the hard work and talent of Londoners, which in turns attracts investment from both inside the UK and around the world.”

The value of goods and services in the capital grew by 3.1 per cent between 2016 and 2018 – compared to 1.8 per cent in the rest of the UK.

In 2017 there were also 19.8 million visitors to the capital who spent £13.5 billion with London businesses.

But Mr Khan warned leaving the EU could change this.

Mr Khan said: “A bad deal or no deal Brexit poses a serious threat to that progress.

“That’s why it’s vital that the public is given a say on the final Brexit deal, and that if we want to protect jobs and growth, any deal struck needs to include membership of the customs union and Single Market.”

Analysis from Mr Khan published last year said following Brexit there could be as many as 87,000 fewer jobs in London by 2020.