He’s not even gotten the job yet, but Boris Johnson’s plans to force through Brexit if he’s appointed prime minister next week have already suffered a major blow. Johnson is nearly certain to become PM next week and he’s repeatedly threatened to suspend parliament to make sure lawmakers don’t stop the country from leaving the European Union on the Oct. 31 deadline. However, that plan was weakened Thursday when lawmakers voted against the government—including more than a dozen members of the governing Conservative party—in favor of a measure that could block that route. If the deadline is reached without parliament backing a deal between the U.K. government and the European Union, the U.K. is scheduled to automatically leave the bloc with no deal. There are enough members of parliament who are against a no-deal Brexit and they could block it if it’s voted upon, but Johnson has said he could avoid that by suspending parliament in the run-up to the deadline. However, the measure backed by lawmakers Thursday requires progress reports to be debated regularly, effectively preventing parliament from being shut down ahead of the deadline, the BBC reports.