Brexit Secretary David Davis called on lawmakers to give the government permission to implement the will of the British people who voted for the U.K.’s formal departure from the European Union.

Davis kicked off two days of debate in Parliament in London on Tuesday and made the case that the issue is straightforward. A rejection of Prime Minister Theresa May’s timetable to trigger Article 50 of the Lisbon Treaty by the end of March would destroy public trust in politicians, he suggested.

“There’s a creeping sense in this country, and others, that politicians say one thing and do another,” a hoarse Davis told a packed House of Commons. “There must be no attempts to stay inside the European Union, no attempts to rejoin it by the back door and no second referendum.”

Read why the Article 50 Bill is a headache for May even as it’s sure to pass.

May had hoped to bypass Parliament and start divorce talks with the bloc on her own initiative. Instead, the U.K. Supreme Court ordered her to draft legislation to get lawmakers to sign off. Last week, the government complied, keeping the bill to just 137 words, with a view to speeding the process along.

That hasn’t stopped opposition lawmakers from proposing more than 130 amendments that fill an 85-page document in a move that could interfere with May’s tight schedule.

Amendments Pile

Speaker John Bercow said he’d accepted a Scottish National Party amendment to halt the progress of the bill, currently in the second of at least 10 steps needed to become law.

“What is the purpose of having a Parliament if it’s not to scrutinize the work of the government?” said SNP spokesman on Europe Stephen Gethins, requesting a written government Brexit plan before the bill is allowed to advance.

Davis coolly told lawmakers the document — known as a white paper — will be published “in due course.” The main opposition Labour Party’s spokesman on Brexit, Keir Starmer, said it should be published by Monday.

Bercow, who selects lawmakers to speak, has allowed for debate to extend until midnight on Tuesday, with a second day of debate on Wednesday, including votes on the amendment and then the bill itself. Almost 100 rank-and-file members have indicated they want to join the debate in the chamber, prompting Bercow to impose a 6-minute time limit on speeches.

No Return

May wants to pull the Article 50 trigger by March 31. Her government hopes the bill’s parliamentary journey will be over by March 7 with a vote in the upper, unelected House of Lords.

If all runs smoothly, May could initiative the legal mechanism for Brexit as soon as March 9, at an EU summit in Malta.

The law is unlikely to be blocked, as the main opposition Labour Party has pledged to support it. But that won’t stop some from trying to influence May’s approach to the Brexit negotiations by stretching out proceedings and seeking some concessions.

For example, among the Labour amendments, there is a demand to secure “full tariff- and impediment-free access to the single market” and a requirement for May to report back to lawmakers every two months during the negotiations.

The bill may pass, but it “does not give the prime minister a blank check,” Starmer said.