It is "too early to say" if a third national lockdown will be needed after Christmas, according to a senior minister.
George Eustice said "you can't rule anything out" when asked by Sky News if the "stay at home" measures could come back into force to keep coronavirus under control.
The environment secretary also said that it may be as late as "next summer" until "we can all start to get back to normal" if a vaccine comes good.
It comes ahead of a crucial vote by MPs on Prime Minister Boris Johnson's strengthened tier system in an attempt to return to a regional approach of rules from 2 December.
He is facing deep unhappiness from many backbenchers, with Sky News calculating more than 50 have gone public with their concerns.
Mr Eustice admitted there were "up to 100" - meaning the government may have to rely on backing from Sir Keir Starmer, who is yet to announce how Labour will vote.
