Energy suppliers have raised concerns over which party will have to pick up potential debts from the government's Green Deal loans.
The scheme aims to provide a million households with loans of up to £6,000 to install energy efficient measures around the home, from new boilers to loft insulation.
Loans are then repaid through savings made on utility bills, but energy suppliers are reportedly wondering who will collect debts if customers are unable to pay back their loans.
According to the Telegraph, a spokesman from Centrica, owner of British Gas, commented that there is "a question" over where the default liability lies.
"There's no solution yet but the government is aware that this needs to be worked through," he told the newspaper.
"Finding a way of fairly sharing this liability between suppliers, finance providers and government will help build confidence in the capital markets which will need to provide tens of billions [of pounds] in the Green Deal."
The Green Deal is anticipated to be launched in 2012 after receiving Royal Assent next autumn.
If you want to find out more about how to compare energy suppliers and save up to £468 in minutes, click here.