FILE PHOTO: Former British Foreign Secretary Boris Johnson leaves the Cabinet Office in London, Britain March 19, 2019. REUTERS/Henry Nicholls

LONDON (Reuters) - Boris Johnson, who was a leading figure in the campaign to take Britain out of the EU, said Brexit was becoming “soft to the point of disintegration” after Prime Minister Theresa May asked to work with the opposition Labour party to secure an exit deal.

Johnson, who quit as Britain’s foreign minister over May’s handling of Brexit, said he was bitterly disappointed with her move on Tuesday and said the country was now likely to remain in a customs union with the European Union, a much softer form of Brexit.

“I think it’s very disappointing that the Brexit process has now been entrusted to Jeremy Corbyn and the Labour party, and I think that the result will almost certainly be, if Corbyn gets his way, that we remain in the customs union,” he told Sky News.

“Brexit is becoming soft to the point of disintegration.”