Faced with continuing opposition from political friends and foes alike, British Prime Minister Theresa May on Monday said she is working on getting further assurances from the European Union to ensure the Brexit agreement is passed in parliament on January 15.

The first day of the winter session saw a repeat of the cut-and-thrust between pro and anti-Brexit forces, as a spokesperson of the European Union in Brussels said the agreement will not renegotiated, “everything on the table has been approved and… the priority now is to await events” in the UK.

May did not respond to an urgent question tabled by Labour leader Jeremy Corbyn “on progress made in achieving legal changes to the EU withdrawal agreement and the timetable in this House for the meaningful vote”, but is due to face him during Prime Minister’s Question Time on Wednesday.

Brexit secretary Stephen Barclay responded to Corbyn, insisting that EU leaders went further than before in giving assurances that the backstop would be temporary during their summit in December.

He said May has had further conversations with EU leaders over the holiday period, adding that the government will set out the assurances it had received before the debate starts on Wednesday.

The UK is due to leave the EU on March 29, adding pressure on various stake-holders to ensure that an agreement is in place to overseen future arrangements between the two that have had a symbiotic relationship since 1973, when the UK joined the EU.

May said she is working on getting further assurances from the EU so she can satisfy recalcitrant MPs. According to her, there has been “some further movement from the EU”, but did not elaborate. The “further measures”, she said, would be set out before the vote on January 15.

As Ireland Prime Minister Leo Varadkar stepped up efforts within the EU to help May gain the support to pass the agreement, fervent Brexiteer Boris Johnson reiterated his opposition to the agreement, insisting that leaving the EU without a deal would be the “closest to what people actually voted for” in the 2016 EU referendum.

A ‘no-deal Brexit’ is deemed to be the worst-case scenario, with serious implications for the UK’s GDP, prices, stock and supply of medicines produced in Europe, movement of British and European citizens within Europe, and the ability of major UK-based banks and financial institutions to operate across Europe.

Johnson wrote in his column in the Daily Telegraph: “Of all the options suggested by pollsters staying in the EU, coming out on Theresa May’s terms, or coming out on World Trade terms it is the last, the so-called no-deal option, that is gaining in popularity”.