Whether it's bluster or not, a dangerous message has been sent to the rest of the world that the UK may be willing to backtrack on important promises.
MPs were supposed to vote either for or against the prime minister's deal in a special weekend session. But things didn't quite work out like that.
What is Boris Johnson's Brexit plan?
How the Brexit 'divorce bill' is calculated and what impact delays will have on it.
Even if the UK decides it can withdraw from the Irish backstop unilaterally under international law, there will be consequences.
What do Theresa May's last minute Brexit guarantees mean for the Irish border?
Even if parliament votes to delay Brexit beyond March 29, the EU27 would have to unanimously agree. Would they?
The UK government has lost a key vote on Brexit – here are the options facing the prime minister.
The prime minister is running down the clock to pressure MPs into accepting her deal. But she's close to losing control.
The EU doesn't want a temporary solution to become permanent.
An EU law expert on what the attorney general's legal advice on Brexit means and its wider significance for the future.
Ministers were found in contempt of parliament on December 4 for not publishing the full legal advice on the Brexit withdrawal agreement.