UPDATE 1-Eurosceptic Rees-Mogg hopeful of changes to UK PM May's Brexit deal

British Prime Minister Theresa May's Brexit deal could be reformed to make it acceptable to "Leave" lawmakers in her party who object to proposals on the Irish border, prominent eurosceptic lawmaker Jacob Rees-Mogg said on Wednesday.

Rees-Mogg, who chairs the pro-Brexit European Research Group (ERG), was among Conservative lawmakers who voted against May's deal when it was overwhelmingly defeated last week, But he said he was more optimistic that changes might be made to the deal that could see it approved by parliament.

"I think at last, things are going our way ... I think there is good news for us to hope that a reformation of this deal could be achieved that could make it acceptable," he added at a think-tank event. "But ... it is not there yet and until it is, people like me will vote against the deal."

Rees-Mogg said changes to the deal would have to have equal legal status to the deal itself, and that the backstop must be somehow removed or nullified to win his vote - something the EU has repeatedly said it is unwilling to consider. If May is able to achieve that and win the support of the ERG head, it could be enough to persuade large numbers of other eurosceptics to vote for May's amended deal and unlock the stymied Brexit process.

Rees-Mogg said attempts under way in parliament to take the exit process out of May's hands and delay leaving the EU were a threat to the British constitution and urged the government to do what ever it took to block them - including suspending parliament if necessary. "If the House of Commons undermines our basic constitutional conventions, then the executive is entitled to use other vestigial constitutional means to stop it – by which I basically mean prorogation," he said, referring to the formal closure of parliament.

(Reporting by William James; writing by Alistair Smout; editing by Stephen Addison)