You may have read in the last day that she won a "revised deal" in Monday night talks with European Commission President Jean-Claude Juncker, but all she really got was repeated assurances that no-one in the EU wants the crucial Irish backstop mechanism (explained here) to be permanent, leaving the United Kingdom indefinitely tied into a customs union with the EU if the two sides fail to strike a new trade agreement in the next couple years.
Having witnessed her initial deal being defeated in the Commons in January by 230 votes (the largest government defeat in over 100 years), the Prime Minister had been negotiating with the European Union for more concessions, in order to push her deal through Parliament.
Mr Derrick said if the prime minister's deal was defeated by only a narrow margin in Tuesday's vote "that might encourage optimism" that a tweaked deal could be agreed before the end of the month.
May said the government would not instruct her own party's MPs how to vote, as would normally be the case.
The prime minister, hoarse after Monday's late-night talks, told MPs: "Let me be clear".
A spokesman for European Council President Donald Tusk, representing EU governments, said Britain would have to provide a "credible justification" for any request for a delay.
Failure could potentially leave the country crashing out with no deal, sparking shockwaves through global markets and possible question marks over May's leadership.
Environment Secretary Michael Gove said it was "make your mind up time" for lawmakers.
MPs will vote on the deal at about 7pm.
Sterling rose on news of the deal but then gave up its gains by mid-morning and was trading $1.3163 at 1040 GMT.
If they don't, May's position as Prime Minister is in serious danger - and Britain will inch towards a no-deal Brexit or, at least, face a delay to the entire process.
British lawmakers, who on January 15 voted 432-202 against May's deal, were studying the assurances and Cox's legal advice before the vote later on Tuesday.
Opposition to May's deal among members of the Conservative Party derives from a belief that it does not offer the clean break from the European Union that many voted for.
"The bulk of Monday's gains have now been handed back and it looks like any hopes of an unlikely victory for the PM's deal later have just been extinguished".
Alan Wager, a Brexit expert at the United Kingdom in a Changing Europe think tank, said the parliament this week could decisively rule out both May's deal and a no-deal departure. May can try to seek further changes from the EU.
"There was a clear concern in [British] parliament over one issue in particular: the Northern Ireland backstop", May said at a joint news conference with European Commission President Jean-Claude Juncker following a meeting in the French city of Strasbourg.
"There will be no further interpretations of the interpretations, no further assurances of the re-assurances".
Whatever Parliament decides this week, it won't end Britain's Brexit crisis.
He said: "Mr Speaker the honourable gentleman asks me about my opinion".
"The positive risk mood is into a second day as optimism about U.S./Chinese trade, a lack of fresh news and Brexit optimism (for once) conspire to keep yen, Swissie, and dollar anchored", said Kit Juckes, a strategist at Societe Generale.
- Major Reputed Mafia Boss Shot To Death Outside His Home
- Trump's ex-lawyer Cohen says testimony 'could have been clearer': lawyer
- With Arab Nationalities Among 157 Victims of Ethiopian Airlines Crash
- Galaxy S10 shipments to be 20 million in H1
- How safe is Boeing's 737 MAX 8 aircraft? | US & Canada
- Usman Khawaja stars again as Australia seal comeback series win over India
- Trump wades into Melania ‘body double’ conspiracy theory
- Nancy Pelosi says impeaching Donald Trump 'just not worth it'
- North Korea Refuses to Hold WHO Regional Session Due to Sanctions
- Facebook and Instagram down in the UAE and elsewhere in the world