Sadiq Khan warns EU not to 'punish' UK over Brexit
The European Union (EU) will make a major mistake if it tries to "punish" the UK during Brexit negotiations, Sadiq Khan has warned.
Speaking in Brussels, The Mayor of London called on a gathering of politicians and business leaders not to "instil fear" during withdrawal negotiations.
He also stressed the economic importance of London to the EU.
Prime Minister Theresa May is due to invoke Article 50 on Wednesday.
Mr Khan said: "Now is the time to be confident in the European Union and to act with confidence. There is no need - as some have suggested - for the EU to send a message, or to instil fear, by punishing the UK.
"Because a proud, optimistic and confident institution does not secure its future by fear."
Mr Khan's speech was intended to put the "emotional" argument for a fair deal between the EU and the UK.
Stressing that all Europeans living in London were Londoners, he said the capital would remain Europe's only global city after withdrawal, and that both sides need each other to boost their own prosperity.
"My city is not only the beating heart of Britain's economy, but the single most important organ for growth across Europe. I say this with friendship and all due respect - but a bad Brexit deal that hurts London would hurt the European Union too," he said.
Such a deal could see major businesses quitting Europe altogether for territories such as Singapore and New York, he added.
Mr Khan also called on the prime minister to make a gesture of goodwill when she invokes Article 50 by offering a "cast iron" guarantee of the rights of 3.3 million EU citizens in the UK.
"We're talking about people's lives and families... and that is just too important to use as a bargaining chip," he added.
London was one of the few areas in England to vote in favour of remaining in the EU in last June's referendum.