No 10 has been reluctantly drawn into a row over whether the public should wear jumpers to keep down their energy bills.

The prime minister's spokesman said it was something people should consider, after the energy secretary, Ed Davey, said he wore jumpers at home to keep the bills down.

But a Downing Street spokesman was later forced to backtrack, saying: "To be clear, it is entirely false to suggest the prime minister would advise people they should wear jumpers to stay warm.

"Any suggestion to the contrary is mischief-making. The prime minister would point people to a range of things being done to help people with their fuel bills, such as legislating to put everyone on the best tariff for them. He believes Labour's 'price freeze' policy is a con, and certainly would not advise people on what they should wear."

The row underlines the acute difficulty the government is facing in responding to the wave of price rises being announced by the energy companies.

David Cameron suggested that customers look for cheaper energy firms after British Gas announced a 9.2% increase. Three more energy firms are still to announce their rises, and the coalition government appears unable to match the headline-grabbing promise by Ed Miliband, the Labour leader, to freeze energy bills for 20 months.

The government acknowledges that Miliband's promise has chimed with the public.

Speaking on the BBC's Newsnight, Davey was asked about people being reluctant to wear jumpers at home to keep warm, and replied: "I'm sure people do wear jumpers. I wear jumpers at home.

"We do need to help people with these bills. I'm extremely worried about them.

"We can use competition in the way we have but we can also make our homes warmer and we can use less electricity and gas by going energy efficient and that's what the government is trying to do."

The prime minister's spokesman said he did not wish to prescribe the actions customers should take, but added: "If people are giving that advice it is something they may wish to consider."

Miliband ridiculed the suggestion. "Their policy was hug a hoodie, now it's wear a hoodie." Shadow energy minister Tom Greatrex said: "It's no good Ed Davey telling people to put on a jumper or shop around. Britain's energy market is broken and people are paying the price for this government's failure to stand up to the energy companies."

British Gas suggested on Thursday that its customers should use less gas and electricity to cope with rising bills.

Ian Peters, the managing director of residential energy at British Gas, said: "A price rise doesn't necessarily mean energy bills have to go up too. The amount you pay depends not on the price, but on how much gas and electricity you use."

Clare Welton, of the Fuel Poverty Action Group, said at the time: "Ian Peters's insinuation that customers should use less gas and electricity to cope with the price hikes reflects just how out of touch the big six energy bosses are with the reality in hard-up households."

Ministers are being urged by some Tory backbenchers to consider a cut in VAT on energy bills as a way of bringing costs down without reducing energy firms' profits, regarded as necessary to invest.

A VAT cut on energy bills has been proposed by Robert Halfon, an influential backbencher seen to be in touch with blue-collar Tory thinking.

The move is illegal under European law, but Halfon is calling on the government to make it a key part of any renegotiation of Britain's relationship with the European Union.

He said: "What we need to do is look at long-term solutions and a cut in VAT on energy bills is the right course. Every 1% you cut from VAT off energy bills saves households £300m."