The UK Government is coming under pressure for more energy-bill support for households.
But Westminster does not have much time to act, as energy firms are due to begin contacting customers within days to warn them of imminent bill increases.
Typical household energy bills are set to rise to £3,000 per year from next month.
The BBC understands the UK Government is reviewing the level of energy support amid calls by campaigners for help to be maintained to prevent bills rising.
From the beginning of April, government support under the energy-price guarantee is due to get less generous.
At the moment, typical bills are limited to £2,500, plus a £400 winter discount, which will also end from April.
Struggle for households
Nearly two million more households could struggle to pay the higher bills, fuel poverty campaigners have said.
Industry group Energy UK said suppliers would be writing to customers soon to let them know how much their bills were going up.
Energy companies are waiting for the government to confirm the level of support households will get before sending the letters, and that is due to happen within days.
Fuel poverty campaigners said the number of households that would have difficulty paying for energy from the beginning of April would rise from 6.7million to 8.4million.
Energy Secretary Mr Shapps has said he is "very sympathetic" to extending government support, and is in talks with Chancellor Jeremy Hunt on the issue.
Mr Shapps also says firms should pass on falling wholesale costs to consumers as soon as possible.
Less borrowing
The Institute for Fiscal Studies said a better economic outlook and falling wholesale energy prices meant the UK was set to borrow tens of billions of pounds less than expected this year.
This means the government has room to extend the energy price guarantee for another three months to cushion the transition to higher bills, its director Paul Johnson told the BBC.
Other organisations, including the Resolution Foundation, have said the government is very likely to extend energy bill support.
Energy UK urged the government to hold the level of support at £2,500 for an average household, "and to announce that quickly so it can be incorporated in customer bills in time for April".
The Treasury declined to comment, including on whether there would be an announcement on further energy bill support in the upcoming Budget.