David Cameron says the UK will take in more unaccompanied Syrian refugee children from Europe, although it has not committed to a specific figure, BBC reported.
Ministers will talk to councils before deciding how many can be resettled.
The UK currently takes children from refugee camps in Syria and its neighbors but there has been pressure to take some who are already in the EU.
Labor said the announcement, made at Prime Minister's Questions, did not go far enough and more action was needed.
Children registered in Greece, Italy or France before March 20 - when the EU struck its refugee deal with Turkey - will be eligible for resettlement, the government said.
It said the retrospective nature of the scheme would avoid creating a "perverse incentive" for families to entrust their children to people traffickers.
It would mean the UK can focus on the "most vulnerable children already in Europe without encouraging more to make the journey", Downing Street said.
Cameron, who has been facing the threat of a Conservative backbench rebellion in a vote next week over the issue, said he had accepted a revised amendment to the Immigration Bill put forward by Labor peer Lord Dubs.
He told MPs: "I am also talking to Save the Children to see what we can do more, particularly about children who came here before the EU-Turkey deal was signed.
"What I don't want us to do is to take steps that will encourage people to make this dangerous journey because otherwise our actions, however well-meaning they will be, could result in more people dying than more people getting a good life."