Campaigners from more than a dozen charities and pressure groups are lobbying MSPs to demand an inquiry into the worsening problem of fuel poverty.

They say that latest figures showed that in 2004-5 there were 419,000 Scottish households in fuel poverty, up from 350,000 the previous year and 293,000 the year before that.

No types of household are immune - but pensioners, single adults and lone parents are worst affected, forcing people to choose between heating their homes or paying for other essentials.

In a joint letter to the parliament's new Local Government and Communities Committee the 13 organisations are urging the Scottish Parliament to set up an inquiry. They point to a commitment in the Housing Act 2001 to eradicate fuel poverty, as far as reasonably practical, by 2016, and say: "A committee inquiry would enable a thorough review of progress, examining what has and hasn't worked, and identify what further interventions are required."

The worsening problem is mainly due to rising fuel costs and, with further increases since 2005, the present level of fuel poverty is estimated to be even higher - at around 600,000 households.

The letter's signatories are Citizens Advice Scotland, Shelter Scotland, Energy Action Scotland, Energywatch, the Child Poverty Action Group Scotland, Capability Scotland, Friends of the Earth Scotland, Help the Aged Scotland, the Poverty Alliance, WWF Scotland, Age Concern Scotland, Association for the Conservation of Energy, and the Church and Society Committee of the Church of Scotland.