Chris O’Shea, chief executive of British Gas owner Centrica, and E.On UK boss Chris Norbury both gave their backing to the proposal on Wednesday.

Appearing in front of Westminster’s Energy and Net Zero Committee, O’Shea said he was in favour of a “progressive social tariff”, while Norbury pointed out that existing support for those struggling with the cost of their bills “does not go far enough”.

Chris O’Shea, chief executive of Centrica, said: “What’s in consumers’ interests is something that is understandable and very straightforward… The easiest thing is abolishing standing charges and have no zonal pricing. And then have a progressive social tariff. Why do people have to play a postcode lottery?

“We think that in order to have the proper smart grid required to keep costs low in the future… everybody should have a smart meter. One of the things we should consider is whether this is a voluntary programme or whether this is a mandatory programme.”

E.On’s UK boss, Chris Norbury, also backed the introduction of a social tariff, adding: “The support that exists for those customers who are on very low incomes does not go far enough… We have called, for example, for a social tariff to support those customers who need it most.”

Their comments were welcomed by Advice Direct Scotland (ADS), Scotland’s national advice service, which has been campaigning for a UK-wide social energy tariff.

The charity has argued that an opt-out scheme – which would automatically put struggling households on the cheapest energy deal – is the only way to effectively end fuel poverty.

The policy could be targeted at those most in need, with eligibility being determined by whether members of a household are in receipt of benefits or are on low incomes.

A poll published earlier this year showed that there is widespread public support in Scotland for the policy, with two-thirds (66%) of those questioned backing it.

Andrew Bartlett, chief executive of Advice Direct Scotland, said: “It is heartening that there is strong support among big suppliers for a social energy tariff, which we believe is the best way of fixing the UK’s broken energy market.

“In the wake of a winter which has once again seen millions of people struggling to afford to heat their homes, we would like to see these warm words translated into concrete action.

“It is time for the UK Government to get around the table with energy suppliers and work out a policy that could be in place before temperatures start to fall again.

“The energy crisis is far from over, with households across the UK building up record levels of debt and still facing much higher costs for gas and electricity than a few years ago.

“Among those who would benefit from a social energy tariff are people with illnesses and disabilities who rely on life-saving electrical equipment to stay alive.”