His comments came in a reply to a letter from Dundee-based MSP Marlyn Glen, who is concerned at a “marked fall” in the number of central heating applications taken forward within the Dundee-centred DD postcode area.

Only 19 new applications were progressed subject to survey in June, the lowest monthly figure for a year.

Ms Glen said she wanted the Scottish Government not to restrict access to the scheme, but to return it to its original format, which ensured eligibility of entitlement for all pensioners.

The MSP is also backing calls that the Scottish Government should be helping pensioners and low income groups from rising fuel prices by setting up a £50 million fund, financed equally by the energy companies and from departmental Holyrood underspends.

Mr Maxwell said he was “deeply concerned” about the impact of rising fuel prices on the effectiveness of fuel poverty programmes, and also the effect they were having on the elderly.

In his letter of reply he said, “I can assure you I intend to continue to bring influence to bear on the UK Government and the energy companies to do all they can to protect vulnerable customers from the impact of rising fuel costs, and to ensure they play their full part in reducing the levels of fuel poverty in Scotland.”

A review of fuel poverty, he said, had shown that more than half of households benefiting from current programmes are not, in fact, fuel poor, and many of those in greatest need were not eligible for help.

Mr Maxwell added, “For this year, priority is being given to those without a central heating system and those with central heating systems that have broken down and who are either in receipt of the guarantee element of Pension Credit or aged over 80.”