LONDON, Sept 7 (Reuters) - British lawmakers, including Conservatives expelled this week from the party, are preparing legal action in case Prime Minister Boris Johnson refuses to seek a delay to Brexit, the BBC reported on Saturday.
An opposition bill which would force Johnson to ask the European Union for an extension to Britain's departure to avoid a no-deal Brexit on Oct. 31 was approved by parliament's appointed upper chamber, the House of Lords, on Friday.
Queen Elizabeth is expected to sign it into law on Monday.
Johnson, a leader of the campaign to leave the EU during the 2016 Brexit referendum, took office in July after his Conservative party predecessor Theresa May quit following three failed attempts to get a deal with Brussels through parliament.
The new prime minister says he wants to take Britain out of the EU on Oct. 31, with or without a deal with the bloc.
Johnson has said he has no intention of seeking an extension and would rather "die in a ditch" than delay Brexit, while on Saturday the Daily Telegraph quoted him as saying he was only bound "in theory" by the new legislation.
The government had no immediate comment on the BBC report, which said lawmakers have lined up a legal team and are willing to go to court to enforce the legislation if necessary.
Johnson says the only solution to the Brexit deadlock is a new election, which he wants to take place on Oct. 15, allowing him to win a new mandate with two weeks left to leave on time.
Two-thirds of parliament's lawmakers need to back an early election, but opposition parties, including Labour, said they would either vote against or abstain on this until the law to force Johnson to seek a Brexit delay is implemented.
Johnson failed to win enough support in a vote on Wednesday for an election, with another vote scheduled for Monday. (Reporting by James Davey; Editing by Alexander Smith)