Work and Pensions Secretary Iain Duncan Smith has refused requests to meet the leaders of a major food bank charity and accused them of "scaremongering", it has emerged.

The Conservative cabinet minister told the Trussell Trust – which operates Wirral’s food bank warehouse collection and distribution centre in Birkenhead - that he denied claims benefits reforms were linked to the rocketing number of people turning to it for help and suggested the organisation was political.

Since April, more than 500,000 people, of which one-third are children, have received emergency supplies from the 400 food banks run by the Trussell Trust charity and it has asked on a number of occasions for meetings with Department for Work and Pensions ministers.

But Mr Duncan Smith criticised the "political messaging of your organisation", which "despite claiming to be non-partisan" had "repeatedly sought to link the growth in your network to welfare reform", according to the Observer.

"I strongly refute this claim and would politely ask you to stop scaremongering in this way," he said in the letter.

"I understand that a feature of your business model must require you to continuously achieve publicity, but I'm concerned that you are now seeking to do this by making your political opposition to welfare reform overtly clear."

Wirral Council leader Cllr Phil Davies is a trustee of the borough's food bank. He told the Globe: "Iain Duncan Smith's comments beggar belief.

"Food banks are now just a part of life, particularly in the North.

"In no way, shape or form is the Trussell Trust trying to score political points.

"The people who help distribute the food, certainly in Wirral, by and large are from local churches; people who genuinely feel sorry for their fellow man and want to help out in some way.

"If Duncan Smith or any of his team would care to visit the food bank, they'd discover that people are literally desperate.

"We can't keep pace with demand, which has soared over the last 12 months.

"The Government simply are not living in the real world. They are talking nonsense."

Trust chairman Chris Mould told the Observer: " We are deeply disappointed, but we are as open as ever to meet ministers in the hope that perhaps the new year will bring a fresh approach to what could so easily have been a fruitful dialogue."

A Department for Work and Pensions spokeswoman said: "The benefits system supports millions of people who are on low incomes or unemployed and there is no robust evidence that welfare reforms are linked to increased use of food banks.

"In fact, our welfare reforms will improve the lives of some of the poorest families in our communities with the Universal Credit making three million households better off - the majority of these from the bottom two fifths of the income scale.

"The Trussell Trust itself says it is opening three new food banks every week, so it's not surprising more people are using them. They also agree that awareness has helped to explain their recent growth.

"The Government has taken action to help families with the cost of living, including increasing the tax-free personal allowance to £10,000 which will save a typical taxpayer over £700, freezing council tax for five years and freezing fuel duty."