James Wharton: EU referendum Bill may fail to pass Commons MPs will debate Mr Wharton's Bill, which stipulates a referendum by the end of 2017, on Friday. Speaking at a press conference in Westminster, Mr Wharton warned that some MPs would use parliamentary tactics to "wreck" his law by tabling numerous amendments for debate. "There will be individual MPs who want to give this Bill a really rough ride," he said. Because it's a private member's Bill, it only has a limited amount of time and the more time we spend discussing amendments the more likely it is that we run out of time. The most difficult amendment to deal with would be one calling for a referendum before the next election, he said, because "many MPs would be sympathetic" to such a move. But this would "fracture" the support for the Bill and create a risk that it would run out of time in the Commons, he said. Mr Wharton accepted that his Bill "cannot bind a future parliament" to hold a referendum and that further Commons votes would be required for a plebiscite to be held. However, passing the Bill would create "a very difficult political environment" in which to overturn it, he said. It would therefore politically be all but impossible to do. John Mills, a Labour donor and businessman, said he wanted his party to support the Bill but Ed Miliband disagreed. The Bill is "much too important" to be used as "a political football," Mr Mills said. Senior Tories claimed any future Labour government that tried to ignore the referendum law could face a legal challenge. The Bill says that any future Foreign Secretary "shall" introduce a parliamentary instrument on a referendum by 2017. That instrument would then be subject to another Commons vote. A Government that failed to allow that vote would risk being ordered to do so by judges, Tories believe. "The bill is clear about introducing that instrument, and any secretary of state that did not would be subject to judicial review," a Conservative source said.