LONDON (AP) — The U.K. Labour Party's chief Brexit adviser says opposition plans to block a "no-deal" Brexit would require postponing the country's departure deadline again so the withdrawal doesn't happen on Oct. 31 as now scheduled. Labour's Keir Starmer told the BBC on Sunday that the legislation to be introduced in Parliament as early as Tuesday will focus on an extension of the deadline to prevent Prime Minister Boris Johnson from leaving the European Union without a deal. "The length of the extension is secondary, frankly. We have simply got to stop us leaving without a deal," he said. Current plans call for Britain to leave the EU by Oct. 31 unless Britain formally asks for its third extension and each of the bloc's other 27 nations agree. Brexit first was set for March 29. A senior Cabinet minister overseeing preparations for leaving with no EU withdrawal agreement declined to say if Prime Minister Boris Johnson's government would abide by Parliament's decision. "Let's see what the legislation says," Michael Gove, a staunch Brexit advocate, said. Gove's refusal to commit to following Parliament's sets up a possible constitutional clash over Britain's plan to leave the European Union to make good on the results of a 2016 referendum. Johnson has vowed to take Britain out of the EU on that day even if there is no deal in place, despite economists warning his determination could have severe costs. The battleground shifts to Parliament when it returns from a lengthy summer recess Tuesday. It was not clear how many members of Johnson's Conservative Party might break with the prime minister over a possible "no-deal" Brexit. Johnson has made plans to shut Parliament for part of the period before the Oct. 31 Brexit deadline. The move would shorten the time his opponents have to try to take control of the Brexit process. Johnson and his top advisers are planning to meet with recalcitrant legislators from his own Conservative Party to try to keep them from supporting the opposition's efforts to prevent "no-deal." EU officials have said they are ready for a "no-deal" scenario if necessary. Germany's foreign minister said in a newspaper interview published Sunday that an orderly withdrawal remains the best option for both sides. But Heiko Maas told the Funke newspaper that "in case a hard Brexit turns out to be unavoidable, Germany is prepared for this scenario." ___ Associated Press writer Geir Moulson in Berlin contributed.