Some 30 Labour MPs and the Green co-leader Caroline Lucas have urged the Government to delay the rollout of the new benefit to avoid delays during the costly festive period.
Pointing to previous waits of up to six-weeks, they said the introduction of Universal Credit in about 50 new areas should be pushed back until the new year.
In a letter to the Guardian, they said: â€œThere is a real worry that the introduction of Universal Credit, at this time, will cause extreme hardship for many people in vulnerable situations, exacerbated by the financial burdens of the festive period.â€
They added: â€œWe understand that the proposed changes were designed to make the social security system simpler, more reactive to an individualâ€™s issues and more efficient.
â€œHowever, evidence from other parts of the country where UC has been introduced already shows that it is far from the efficient system trailedâ€¦
â€œThe current timetable will cause our residents severe hardship over the months which are most financially difficult.
â€œWe urge that you do not roll this system out in November and December, but look to a date later in 2018.â€
The signatories include Shadow Cabinet minister Kate Osamor, as well as prominent backbenchers Stella Creasy, Alison McGovern, John Mann and Jon Cruddas.
A recent Citizens Advice survey of 800 claimantsÂ in trial areas found 39% were waiting six weeks for the first payment and 57% were forced to borrow cash.
A DWP spokesman said: â€œWe are rolling out universal credit in a gradual, safe and secure way and the majority of people are managing their budgets well.
â€œThe best way to help people improve their lives is to help them into work, and under universal credit people are moving into work faster and staying in work longer than under the old system.â€
Nearest tube: Elephant & Castle underground station (Northern and Bakerloo lines).
Nearest Railway Station: Elephant & Castle
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