Sir Keir Starmer has said Labour will not be "voting down" the 22:00 curfew for pubs next week, instead saying the rule "needs to be reformed".
The Labour leader criticised the "up, down, take-it-or-leave-it vote" due on Tuesday, saying it would leave no restrictions in place if lost by the government.
"That's not what we want," he said. "That's not in the nation's interest."
It comes amongst growing criticism of local lockdown policy from Tory MPs.
A number of backbench rebels are expected to vote against the curfew measure when it comes to the Commons next week.
But BBC political correspondent Jessica Parker said the statement from Sir Keir "takes the pressure off the government", as without Labour, the rebels are unlikely to get the numbers to vote down the curfew.
A senior government source told the BBC: "Keir Starmer should be supporting measures to protect the NHS and save lives instead of playing politics in the middle of a global pandemic."
Earlier this week, Tory rebels tried unsuccessfully to persuade Labour to vote against continuing with the "rule of six" restriction socialising in England.
Despite agreeing with many of their criticisms about the lack of scientific evidence for the rule, shadow health minister Justin Madders abstained, along with other Labour MPs.
Sir Keir has widely supported government lockdown measures during the pandemic, but has been increasingly critical around the "lack of evidence" for the moves.
He previously refused to say which way Labour would vote on the curfew rule, saying the prime minister "needs to make his case" about how the 22:00 cut-off reduces transmission and "the ball very firmly is in his court".
All pubs, bars, restaurants and other hospitality venues in England have been required to close at 22:00 since 24 September, as part of a package of measures to try and contain the rise in positive results.
A Downing Street spokesman said on Thursday that early data showed a "significant proportion" of coronavirus exposure was being seen in the hospitality sector.
No 10 said it was even more pronounced in younger age groups, where infections are rising most rapidly - but they said the data was "new" and more evidence is being gathered.
But speaking on a visit to Wiltshire, Sir Keir called for the government to acknowledge the curfew wasn't working as anticipated, adding: "There's a smarter way of doing this".
Meanwhile, Communities Secretary Robert Jenrick has confirmed further restrictions are expected to come into force in England "in the coming days" after a surge in cases across the country.
The BBC was told pubs and restaurants could be closed in the worst-affected areas, as well as a ban on overnight stays away from home.
A new three-tier system for local lockdowns is also likely, where different parts of the country would be placed in different categories - although ministers are still discussing the precise details of the toughest level of restrictions.
The prime minister's official spokesman said the government was keeping the data on the spread of infection under "close review" and considering a "range of options" to reduce the spread of the virus.
He added: "If we feel like we need to take further action then we will do so."