Two more UK energy firms have ceased trading amid soaring wholesale energy prices.
Pure Planet, which is backed by oil giant BP, and Colorado Energy join a number of small energy firms that have gone bust recently.
Pure Planet said it had been caught between rising costs and the UK's energy price cap, which limits what companies can charge consumers.
This had left its business "unsustainable", it said.
Customers of both companies will be moved to new suppliers.
Energy firms' collapse hits 1.5 million customers
Pure Planet and Colorado Energy are the latest casualties of a global spike in gas prices.
Pure Planet supplies gas and electricity to around 235,000 domestic customers, while Colorado Energy supplies gas and electricity to around 15,000 domestic customers.
Energy regulator Ofgem will now find a new supplier for those customers, who are asked to do nothing until the transfer takes place in the coming weeks.
Today's developments bring the number of customers affected by the current wave of energy company collapses across the UK to around two million.
Ofgem said on Wednesday that the unprecedented increase in global gas prices in recent weeks was putting financial pressure on suppliers.
"Ofgem's number one priority is to protect customers," said Neil Lawrence, director of retail at Ofgem.
"We know this is a worrying time for many people and news of a supplier going out of business can be unsettling.
"I want to reassure affected customers that they do not need to worry: under our safety net we'll make sure your energy supplies continue."
Mr Lawrence added that if customers have credit, the funds are protected, so customers will not lose the money that is owed to them.