BIRMINGHAM, England (Reuters) - Three British government ministers privately support the idea of holding a second referendum on the final Brexit deal, a former junior minister said on Monday.

Conservative lawmaker Phillip Lee, who resigned from the justice ministry in June over the government’s handling of Brexit, told a packed pro-EU event on the sidelines of the party’s annual conference that the ministers had told him so in private conversations.

“I suspect there are significant numbers of colleagues who can see the argument for a second referendum, I know of three ministers who do,” he said in response to a question about how many Conservative lawmakers support a so-called people’s vote.

Lee did not identify the three ministers.

Prime Minister Theresa May has repeatedly ruled out holding a public vote on any final Brexit deal but the opposition Labour Party increased pressure on her last week by saying it would keep the option of another referendum on the table.

With six months to go until Britain is due to leave the European Union, May is yet to reach an exit deal with the bloc, and both Labour and many lawmakers in her own party are threatening to vote against any deal in parliament.

Justine Greening, who served as education minister under May until January, said May’s so-called Chequers proposals would not get through parliament, and neither would a Canada-style free trade deal preferred by some Brexit campaigners.

“Parliament is at a stalemate,” Greening told the event. “I think there is a growing body of Conservative MPs who have thought their way through this, as we have, and reached the same logical conclusion that a referendum is the only way to unlock a parliament stalemate.”

“It is a question of when they make their views known.”