Christian campaigners have challenged the Chancellor not to hide how his upcoming budget will affect poorer families.

The director of Church Action on Poverty, Niall Cooper, and the general secretary of Quaker Peace and Social Witness, Helen Drewery, were among the signatories of a letter that urged the government to "provide a transparent account" of the effect of its budget tomorrow.

In last summer's emergency budget George Osborne removed the obligation to provide a "distributional analysis" which details the implications of its policies on households of all incomes.

In a letter to the Guardian Cooper and Drewery, alongside six other campaigners including chair of The Equality Trust, Sean Baine, and chief executive of Church Poverty Action Group, Alison Garnham, called this a "serious mistake".

They accused the government of hiding a "vital function".

"In order to tackle poverty, inequality, and other social ills, it is important that government publishes its most robust data to provide an accurate account of the scale of these problems," they wrote.

"This includes data on whether government policies effectively alleviate or exacerbate them.

"We therefore call on the government to reinstate its publication of a distributional analysis at the forthcoming budget, to provide a transparent account of how it will affect different households throughout the UK.

"This is matter of both clarity and good governance."

Osborne will announce his new budget on Wednesday amid gloomy economic forecasts and instability in global markets. Christian campaigners have suggested 600,000 people could be affected by upcoming cuts to disability benefits.