Khan said Britain was now facing either a bad deal or a no-deal Brexit, both of which were "incredibly risky".
International Monetary Fund chief Christine Lagarde said Monday that "all the likely Brexit scenarios will have costs for the United Kingdom economy", and a no-deal Brexit "would impose very large costs". "I think that the alternative to that will be having no deal", she said, in reference to her so-called Chequers plan which had deeply divided different sections of the political divide.
Britain is to due to leave the European Union at the end of March, but Khan warned the country now faces two "incredibly risky" options ― both of which could have devastating impacts on the economy and people's living standards.
Many economists say leaving the European Union without a deal would be economically devastating for Britain.
With May's plans in doubt, many British ministers have outlined the damage that they say a disorderly "no-deal" Brexit would do to the world's fifth-largest economy and its reputation as a politically stable haven for investment.
'But the Chequers approach is the right one for now because we have got to make sure that we respect that vote and take advantage of the opportunities of being outside the European Union'.
Typhoon makes landfall in China after killing 59 in Philippines
It made landfall on the coast of Jiangmen city, in southern China's Guangdong province, Sunday evening after battering Hong Kong . Images of a residential apartment and an office building with their windows blown out circulated on social media in Hong Kong .
Britain's Prime Minister Theresa May leaves 10 Downing Street in London on September 12, 2018. "One of them is the issue of how to avoid a hard border between Ireland and Northern Ireland".
The London Mayor explained that with negotiations in disarray and the very real prospect of a "no deal" Brexit - which would be disastrous for Britain, he now believed that the British people should also be given a say on whatever Brexit Theresa May's government managed to negotiate with the other European Union member states.
Johnson, May's former foreign minister, attacked her Brexit plans on Saturday and warned the United Kingdom was heading for a "car crash" Brexit.
"The whole thing is a constitutional abomination, and if Chequers were adopted it would mean that for the first time since 1066 our leaders were deliberately acquiescing in foreign rule", Johnson said, referring to the 11th Century invasion which established Norman rule over England.
Johnson, May's former foreign minister, scolded May for her handling of negotiations on the future of the border between Northern Ireland and the Irish Republic. Johnson wrote in Monday's Daily Telegraph that May's Brexit negotiations were heading for a "spectacular political auto crash" that would leave Britain in "the ditch with a total write-off of Brexit".
"I don't want manufacturers to feel that they've got to operate under all sorts of different rules, because that complicates life for them and that potentially means business leaving this country", she said.