LONDON (NYTIMES) - Opposition and rebel lawmakers wrested the legislative agenda from British Prime Minister Boris Johnson on Tuesday (Sept 3) and then introduced a measure that would require the government to request an extension of the deadline for the country's withdrawal from the European Union if no agreement is reached.

Mr Johnson had been bracing for this confrontation with lawmakers after they returned to work a week after his shocking announcement of a suspension of Parliament this month.

That move, which had limited the time for lawmakers to find a way to prevent Britain from crashing out of the EU on Oct 31 without a deal, angered the opposition and aggravated divisions within his own party.

Mr Johnson is now expected to call for a snap election on Wednesday, dissolving Parliament just as its summer break ends.

Here's what you need to know after another day of political turmoil in Britain.

WHAT IS THE SHOWDOWN ABOUT?

Britain is scheduled to leave the EU on Oct 31, and Mr Johnson has vowed that it will happen on time, with or without a deal.

But opposition parties and a significant number of rebels in his Conservative Party are adamantly opposed to a no-deal Brexit, which they say would be chaotic and economically damaging in the short and long term.

Seeking to tie Parliament's hands, Mr Johnson said last week that he had asked the Queen to prorogue, or suspend, Parliament later this month, cutting short the already tight time frame for lawmakers to come up with a way to prevent Britain from crashing out of the EU with no agreement in place.

The move left lawmakers scrambling for a way to weigh in on the most momentous decision the country has faced in its recent history. They decided to ram through legislation requiring the government to seek a Brexit extension if it has not reached an agreement with the EU on withdrawal by the deadline.

But on Monday evening, in an address outside No. 10 Downing Street, Mr Johnson made it clear that he was unalterably opposed to seeking another extension.

"I want everybody to know there are no circumstances in which I will ask Brussels to delay," he said, as a crowd of protesters shouting "stop the coup" was audible in the background. "We are leaving on Oct 31, no ifs or buts."

CAN BORIS JOHNSON STOP HIS OPPONENTS?

He is certainly trying. The outcome of Tuesday's legislation hinged almost entirely on opponents of a no-deal Brexit in his own party. Mr Johnson threatened to kick those rebel lawmakers out of the party.

By insisting that he will not request a Brexit extension, the Prime Minister made clear that if he lost the vote, he would seek to dissolve Parliament and call a snap election. That is now expected to happen on Wednesday.

A government official confirmed as much on Monday evening, saying an election would be held around Oct 14-15, about two weeks before the withdrawal deadline. It would be the third general election for British voters in just more than four years.

At the start of the day on Tuesday, Mr Johnson held a precarious, one-vote majority in Parliament, if only with the 10 seats of a conservative party from Northern Ireland. But by the end of the day, after the defection of a Conservative member of Parliament, Mr Phillip Lee, to the Liberal Democrats, that was gone.

So although the election under such circumstances might prove chaotic, Mr Johnson is betting he can win a strong enough mandate to push through Brexit by Oct 31, "do or die", as he often says.

WHAT DOES BORIS JOHNSON REALLY WANT?

Since his first address to Parliament as prime minister in July, Mr Johnson has insisted that he is prepared for Britain to leave the EU on Oct 31 with or without a deal. He says this stance gives him increased bargaining power in negotiations with Europe to secure a new agreement that is more beneficial to Britain.

Even as he has raised the stakes at home, Mr Johnson has ramped up discussions with Brussels through his Brexit negotiator, Mr David Frost, in an attempt to find an alternative to the Irish backstop, an element of the proposed Brexit deal that has been a major sticking point.

But critics say there is not enough time to come up with a solution to the complex issue before the end of October. And many say the negotiations - and Mr Johnson's call for Brexit at any cost - are just ruses, aimed at a general election in which he can frame himself as the candidate who made an earnest effort to deliver on the will of the people versus the career politicians and others in Westminster.

HOW IS THIS PLAYING OUT LOGISTICALLY?

Lawmakers returned to Parliament on Tuesday after weeks away and asked the Speaker of the House of Commons, Mr John Bercow, for an emergency vote to allow opposition members to "seize control of the order paper" - a move that gave them control of the daily agenda.

Mr Bercow who has openly criticised the Prime Minister's decision to prorogue Parliament, approved their request, which led to a vote on Tuesday night.

That set the stage for Mr Johnson to ask Parliament to call a general election. This requires a two-thirds majority, and the opposition Labour Party, while welcoming the idea of an election, says it might not support such a request.

WHAT WILL THIS MEAN FOR BREXIT?

With the value of the pound plunging through the US$1.20 (S$1.67) barrier for a time on Tuesday morning, it is obvious what currency traders think: more confusion and uncertainty, which is bad for business, and possible chaos, with shortages of food, medicines and fuel, which is bad for everyone.

What keeps analysts and business leaders up at night is the compressed schedule. If a general election is held on Oct 14, a new government would have only 17 days to deal with things before the Brexit deadline.

Making matters even more hectic, the EU is holding a summit on Oct 17 and 18, at which the leaders are to consider what to do about Brexit. That assumes, of course, that the government in place has a plan to consider.

Much will depend on which party, or parties, form the government and with how much of a mandate. If the Conservatives win, Mr Johnson will claim a mandate for leaving, with or without a deal.

But if the opposition Labour Party wins - perhaps with the backing of other opposition parties like the strongly anti-Brexit Liberal Democrats - then Mr Corbyn is likely to seek an extension from Brussels, allowing time to either negotiate a new deal with the Europeans or, potentially, call a second referendum.