Brexit-supporting rebels in British Prime Minister Theresa May's Conservative Party said on Wednesday they would vote down her European Union divorce deal when she brings it back to Parliament next month.

Britain had been due to leave the EU on March 29 but Parliament has three times rejected the withdrawal agreement May struck with Brussels. The United Kingdom is now scheduled to leave, with or without a deal to smooth the exit, by Oct. 31.

Defeat in the vote would likely spell the end of May's divorce deal and probably her prime ministership.