Campaigners have warned the Government it would be “indefensible” to use the latest lower inflation figures to uprate benefits, describing it as a “big cut” for struggling families.

Chancellor Jeremy Hunt must raise benefits by inflation “in the usual way”, using the September figure of 6.7%, charity Action for Children has said.

Organisations have expressed concerns about reports that the Government might use October’s lower figure of 4.6%.

The Joseph Rowntree Foundation (JRF) said that, should this happen, it would be a move to “fiddle the figures and hide a big cut”.

Treasury minister Gareth Davies refused to guarantee the September figure would be used.

He told ITV’s Good Morning Britain: “I am not going to speculate what may or may not be in the autumn statement.

“But I would point out that we did uprate benefits by quite some considerable margin earlier this year. But it’s not appropriate for me to comment ahead of the autumn statement.”

Organisations working with families and children have already expressed concern in recent weeks that benefits are not covering costs for some of the lowest-income households.

Last month, a letter from Save the Children, the Trussell Trust food bank network, the JRF, Action for Children, Citizen’s Advice and The Children’s Society, urged Conservative MPs to demand Mr Hunt “do the right thing” by uprating benefits at least in line with September’s inflation figure.

JRF chief analyst, Peter Matejic, said many families “live in a world where their income, in many cases, simply doesn’t cover costs, while the Government talks about cutting their support further”.

He added: “It’s indefensible that the Government is reportedly considering cutting the benefits of struggling families worried for their future, with news stories suggesting it plans to use today’s figures, instead of last month’s, to fiddle the figures and hide a big cut.

“In the upcoming autumn statement benefits must be increased in line with inflation and Local Housing Allowance (LHA) must be unfrozen to support private renters with their housing costs.

“The Chancellor should also take steps to ensure that Universal Credit, at a minimum, always enables people to afford the essentials.”

Action for Children’s chief executive, Paul Carberry, said while the inflation fall might be “mission accomplished for Government”, the cost of living crisis “is getting worse for many of the families we see every day”.

He added: “With winter approaching, the continued financial pressures on low-income parents will only get worse, meaning yet more children going cold and hungry.

“The Chancellor must use the autumn statement to protect families with children from these intense and ongoing pressures on household finances. At the very least, he must raise benefits by inflation in the usual way using the September figure and reform Cost of Living Payments to account for family size.”