The education secretary has said he would "certainly hope" schools in England could reopen before Easter.
Gavin Williamson said he was "not able to exactly say" when pupils would go back but schools would be given two weeks' notice before reopening.
Primary and secondary schools remain closed, apart from to vulnerable pupils and the children of key workers.
Downing Street said the prime minister wanted schools to open as quickly as possible but would follow the evidence.
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