Thousands of ethnic minority Londoners will to be disenfranchised by plans to reform the electoral system, Sadiq Khan claimed on Thursday.
The mayor said the Elections Bill was a “manifesto for voter suppression”.
He also tore into moves to replace the supplementary vote system, used to elect the mayor, with first past the post.
Ministers said introducing voter ID will stop people pretending to be someone else when they vote. But critics said there have been just three convictions for voter impersonation since 2016.
Mr Khan said: “The Tories’ own figures tell us that 39 per cent of British Asians and 47 per cent of black British people don’t hold a full driving licence.”
The Government said people without ID will be able to apply for a free voter card if they don’t have a passport or driving licence.
The Elections Bill was introduced by ministers last July after Mr Johnson pledged during the 2019 election campaign to protect the integrity of Britain’s democracy.
Mr Khan said the move to require people to provide official identification such as a passport or driving licence will have a chilling effect on democracy, especially in London and among ethnic minorities.
The Mayor’s office said more than 2.5 million Londoners don’t hold a driving licence while around 550,000 do not hold a passport.
Mr Khan said: “The Bill’s proposals, including the requirement for voters to present photo ID, seem specifically designed to disenfranchise swathes of the electorate.”
The Government rejected Mr Khan’s criticisms insisting people without ID will be able to apply for a free voter card if they don’t have a passport or driving licence.
A spokesman said: “We cannot be complacent when it comes to ensuring our democracy remains secure. Our Elections Bill will stamp out the potential for voter fraud.”
The Tory peer Lord Hayward added: “We are virtually the only country in the western democratic world which doesn’t require some form of personal identification.”
But the bill has raised other concerns.
Under the legislation, the Government would also be able to set a strategy and policy statement for the Electoral Commission – a move seen by critics as a threat the electoral watchdog’s independence.
Labour MP Cat Smith, a former shadow minister for young people and voter engagement, told the Standard: “It’s completely inappropriate for the Government to give strategic direction to the regulator. If we pass the legislation in its current form, you can’t guarantee everyone will be a ‘good chap’ later on and do what’s right.”
Ms Smith also echoed the London Mayor’s concerns over the removal of a 15-year limit on registration for overseas voters.
At the moment overseas nationals must register to vote every year and can do so for 15 years, but if the bill is passed, the 15-year cap will be removed, while Britons will only need to re-register every three years and can qualify to vote if they have resided in the UK at any time previously.
With registered voters being able to donate to political parties, the MP for Lancaster and Fleetwood warned the Government could open the UK up to overseas influence and remove safeguards to stop electoral fraud.
“If you remove it, there is no safeguard against electoral fraud. Why would we make our system more vulnerable. If we do this, we could see foreign states push huge amounts of money into political parties or referendums.”