Sacha Lord has announced he is working with lawyers on a plan to help hospitality businesses recover hidden commissions paid to brokers by energy companies.
The night-time economy adviser for Greater Manchester said it was "a national scandal" that had happened "on [Ofgem's] watch".
He added that the issue could be on the scale of the PPI scandal, where millions of people were paid £26b in compensation after being mis-sold insurance between 1990 and 2010.
Lord has been working with JMW Solicitors, the law firm he used to force the government to drop its rule that hospitality venues could only serve alcohol alongside a ‘substantial meal' during coronavirus restrictions in 2021.
He also used the legal team to challenge the 10pm curfew restriction during the pandemic.
Lord wrote on Twitter this morning: "We're about to claw back money [hospitality businesses] paid under duress."
He added: "Many hours have already gone into this and we are now making great progress in finalising a plan to help hospitality businesses recover hidden commissions paid to brokers by energy companies.
"This is not just restricted to Greater Manchester, we've opened this up to the whole sector across the UK. Even businesses that have sadly had to close."
JMW Solicitors said: "We are pleased to work with Sacha Lord once again."
In February, law firm Harcus Parker said energy firms could face a £2b legal challenge from thousands of businesses over claims they inflated customers' bills to pay "secret commissions" to third-party brokers.
Harcus Parker has written to multiple energy companies in the first step in a separate group litigation and claimed in some cases the hidden payments could have inflated energy bills by more than 50%.
Lord said he would post another update in the next two weeks with details of how operators could make a claim.
Ofgem has been contacted for comment.