The prime minister has been accused of acting “like a second-hand car salesman” over the Brexit trade deal.
The UK could leave the transition period on 31 December without a deal after talks with the EU hit a snag over fishing, governance rules and dispute resolution.
On Wednesday during Prime Minister’s Questions (PMQs), Boris Johnson was pressed over promises he made regarding an agreement last year.
Labour MP Mark Hendrick said: “He promised an oven-ready deal with the EU to win the 2019 general election and we look like having no-deal.
“When will the prime minister follow through and deliver on these promises instead of behaving like a second-hand car salesman.”
He was also accused of putting the Good Friday Agreement in jeopardy.
Johnson responded: “If he the honourable gentleman is saying he wants to keep this country in the EU… then he’s going to be sorely disappointed and so will the party opposite.”
Watch: Brexit briefing a month before the end of the transition period
SDLP MP Claire Hanna (Belfast South) also suggested the UK government appeared to have an “unlimited disregard” for the Good Friday Agreement.
She made the claim in the Commons as she said people in Northern Ireland are desperate for “certainty” and “stability” ahead of the end of the transition period.
Hanna also pressed Northern Ireland secretary Brandon Lewis to rule out any undermining of the Northern Ireland Protocol.
Lewis said the clauses in the UK Internal Market Bill would protect and deliver on the Good Friday Agreement “to ensure there are no borders”.
The bill contains clauses ministers say are needed to protect Northern Ireland's delicate status as part of the UK, but would also break international law in a "specific and limited" way.
The bill suffered a heavy defeat in parliament's upper chamber last month but the government is set to retable it in the House of Commons, where it had previously passed by 340 votes to 256.
US president-elect Joe Biden has made it clear he will not put up with a hard border in Ireland.
He discussed Brexit with Johnson earlier in November during one of his first phone calls to other world leaders after winning the election, warning him Brexit must not jeopardise the Northern Ireland peace process.
Last week he said: “The idea of having a border north and south once again being closed is just not right, we’ve just got to keep the border open.”
Johnson suffered the largest Tory rebellion of this parliament over the new coronavirus tier system on Wednesday when 55 Conservatives voted against the rules.
But the measures passed 291 votes to 78 – a government majority of 213 – with Labour ordering its MPs to abstain after party leader Sir Keir Starmer warned the plans posed a “significant” health risk.
Starmer took a lead over the PM in a Mail on Sunday and Deltapoll survey for the first time since March last year.
Watch: How England's new three-tier COVID system will work