British Prime Minister Boris Johnson on Wednesday accused caterers of insulting families with meagre food packages paid for by the government to make up for meals poor children are missing in schools shut by the coronavirus.
Some of the food parcels were "an insult to the families that have received them", Mr Johnson said.
Images were posted on the internet showing packages that appeared to contain food worth only a fraction of the amount that the companies were paid to provide.
One Twitter user posted a photo of a parcel containing a loaf of bread, some vegetables, pasta, beans, cheese and a few snacks.
The supplier, Chartwells, a unit of the Compass Group, apologised and said it would refund some money to schools.
Britain provides free lunches to poor children in primary schools, and turned to private companies to replace them with food packages after it abruptly shut all schools last week.
Manchester United soccer player Marcus Rashford, 23, who has become a prominent campaigner against child poverty, said he had discussed the lean packages with Mr Johnson on Wednesday.
"He has assured me that he is committed to correcting the issue with the food hampers and that a full review of the supply chain is taking place," Rashford tweeted.
Last year he led a campaign to pressure the government into providing meals during school holidays.
The government initially resisted but then agreed, and praised Rashford for his advocacy.
CCLA, Britain's largest investment manager for charities, called on Compass Group to answer questions about the provision of Chartwell food parcels.
"The company must be completely transparent, make adjustments and improvements as required and move quickly to restore faith in its business," said James Corah, head of ethical investment at CCLA.
Compass did not immediately respond to a request for comment.