Matt Hancock has said the government faces a “challenging decision” as to whether to press ahead with ending England’s lockdown on June 21.
Boris Johnson is due to reveal next week whether stage 4 of his roadmap will go ahead.
But spike in Covid cases threatens to derail the prime minister’s plan to end all social distancing rules.
Speaking in the Commons on Tuesday, Hancock said the government would be “guided by the science”.
“We face a challenging decision ahead of June 21,” he said. “These are difficult judgements.”
The health secretary also revealed a “strengthened package of support” will be provided for Greater Manchester and Lancashire to tackle a rise in the Delta variant of coronavirus.
Hancock said it would include “rapid response teams”, extra testing, military support and supervised in-school testing.
Earlier on Tuesday former Tory health secretary Jeremy Hunt, who now chairs the Commons health committee, said any delay to easing lockdown would only be for a couple of weeks owing to the success of the vaccination programme.
Hunt said he was “feeling quite optimistic that we are going to see the restrictions lifted” as “being double-jabbed” works against the Delta variant.
“So, if ‘Freedom Day’ ends up being put back a couple of weeks so we can get more people double-jabbed, I think it will only be a temporary setback,” he told Times Radio.
He added: “I think we are on the way to getting back to normal.”