A coalition of UK Churches is encouraging people to add Work and Pensions Secretary Iain Duncan Smith to their Christmas card list and include a personal greeting asking the minister to ensure that every family and child has enough this Christmas.

The One More Card Campaign is an initiative by the Baptist Union, the Methodist Church, United Reformed Church and the Church of Scotland.

Paul Morrison, Policy Adviser for the Methodist Church, said: "The campaign will show care both for the families affected by the changes to the benefit system and also towards those who run the system reflecting the important job they do.

"No one should grow up in a family that does not have enough to afford the basics of life. It is a message that has particular resonance at Christmas and I am sure shared by people in and out of churches."

Faith groups have joined together to argue that measures contained within the Welfare Reform and Work Bill will break the historic link between the support that is offered to a family by the benefit system and the family's actual needs.

The "two child rule" announced by the Chancellor of the Exchequer in July means that starting from 2017, families with three or more children will receive the same support from tax credits or universal credit as a family with two children.

The move was met with fierce criticism from charities and anti-poverty campaigners, with the chief executive of The Children's Society, Matthew Reed, saying: "The announcement to limit child tax credits to two children is effectively a two child policy for the poorest families."

Morrison said: "One More Card forms part of the Enough campaign supported by many UK Churches. These campaigns have a simple message: a family's material needs, especially the needs of children, should be met where possible. This is a principle central to the benefit system and which the Welfare Reform and Work Bill currently before Parliament is proposing to change."