Food banks are "running out" as the Government's flagship welfare reforms are being rolled out, Labour has warned.
Shadow work and pensions secretary Debbie Abrahams made the claim as she renewed calls for ministers to pause and fix Universal Credit during an emergency Commons debate.
MPs last week supported an Opposition-led non-binding motion which asked for the programme to be halted, by 299 votes to zero, with the Conservatives abstaining.
Labour wants the Government to outline what action it intends to take following the vote.
Speaking in the Commons, Labour former minister Angela Eagle said a pause in UC was "urgent".
She added: "In Wallasey the roll-out will begin halfway through November, six weeks later it's Christmas.
"The (Department for Work and Pensions) will not be open on Christmas Day, which means many of my constituents will have to wait until the new year for any assistance, which is why our local food bank is looking to collect 15 tonnes of extra food to deal with the demand."
She urged the Government to listen to Parliament and take action to "alleviate this obviously avoidable hardship".
Ms Abrahams, in her reply, said: "Food banks are running out of food as this scheme is being rolled out.
"What is going to happen to these families that desperately need this financial support?"
Labour also questioned why Work and Pensions Secretary David Gauke was not present in the Commons for the debate, with his ministerial colleague Damian Hinds in position.
Concerns include the time it takes for new claimants to receive their first payment under UC, with MPs having warned that the six-week wait has been causing issues.
Ms Abrahams labelled this "particularly draconian" and said it had a real impact on claimants.
Conservative MP Heidi Allen (South Cambridgeshire), who has repeatedly raised concerns about UC, earlier asked the Labour frontbencher: "The moment, it feels to me, to pause Universal Credit determined by statutory instruments, as she will know, has passed.
"There is another opportunity in January when there will be another month in-built pause into the system.
"If we could find compromise with the Government and make some significant changes to the policy, such as reducing the six-week wait to four, would that be acceptable from the Opposition's point of view?"
Ms Abrahams replied: "It needs to happen urgently. This is already happening - already 55 areas this month are having full service rolled-out to them.
"The cold months are upon us. Christmas will be around the corner any moment now. We need an urgent response now."
Tory MP Simon Hoare (North Dorset) said the Government has had "just three sitting days" to reply since last week's vote.
Ms Abrahams asked the Government to end the six-week wait for some first payments and bring them forward by at least one week, and said bringing them forward by two weeks would make a "huge difference to people".
She also called for alternative payment arrangements to be offered to all claimants when they make a claim - such as fortnightly payments, split payments and payments directly to the landlord.
And she asked the Government to reconsider the "nonsensical" plan to close one in 10 job centres while rolling-out Universal Credit, and to invest in the programme to, for example, eliminate the two-child limit.
Mr Hinds urged caution in "ascribing the reasons for the usage of food banks to individual or simple causes".
He was asked by Labour former minister Frank Field if concerns that food banks would need more food in the coming year were "scaremongering" or if the Government would not be able to deliver on Universal Credit "without reducing them to hunger".
Mr Hinds said: "No we do not expect for these things to happen because we want the system to work as well as it possibly can.
"It continues to improve in its performance and we continue to evolve and improve the system."
Mr Hinds said the "general commentary" from last week's motion had been heard, adding: "I've also taken away a number of points that were raised for action.
"There were some individual cases and also policy and process matters. These included how we can improve arrangements for direct rent payments, our approach in cases of domestic abuse, process for housing benefit debt recovery.
"There were also informational issues that came up. In response to (Richard Graham, Tory MP for Gloucester) I committed to publishing the roll-out schedule for the landlord portal and trusted partner status."
Mr Hinds said staffing levels are increasing to complement the roll-out of UC.
He added the Government's gradual approach means it can "continually adjust and evolve" the programme.
SNP social justice spokesman Neil Gray said: "If the Government is serious about Universal Credit and is serious about tackling inequality, they need to get serious about fixing the major problems with Universal Credit as it's currently being rolled out.
"Parliament has spoken on Universal Credit, it's time the Government acted to fix it."