Boris Johnson has said the government has not yet decided on its strategy for easing the coronavirus lockdown.
The prime minister is under pressure from the public and many of his own MPs to outline his plan for taking England out of its third national lockdown.
He has said he will lay out his road map for easing restrictions next Monday.
However, he told a Downing Street briefing that the government has not yet decided what the lockdown lifting will look like.
Johnson said on Monday he wants the current national lockdown, which he announced at the beginning of January, to be the last.
Watch: How might the road map out of lockdown look?
But he admitted he could not offer a “cast iron guarantee” there will not be another lockdown.
He said: “We don’t really yet have sufficient clarity on the data to be sure now, today, as of this Monday 15th, exactly what we’ll be able to say to you on Monday 22nd.
“That’s because the data becomes clearer with every day that passes and we have to continue to evaluate.
“And also, to be absolutely clear, these decisions we will take in the course of this week but they are not yet taken.”
Johnson advised the public to take media reports about the lockdown easing “with a pinch of salt”, saying: “This is still speculation.”
He added: “When I explain on the 22nd what we are going to do you will be hearing it directly from me.”
Vaccines minister Nadhim Zahawi declined to say how low coronavirus infections must be in order to allow the lockdown to ease.
He told Sky News on Tuesday: “The prime minister is right to say that where we are today in terms of number of people in hospital, in terms of case numbers per day, it’s still far too high and we want to make sure we bring that right down.
“But I wouldn’t want to speculate on this until we see more data.”
The PM's comments came after The Times on Monday reported that the government was considering plans to permit some trips at Easter, which takes place at the start of April this year.
Elsewhere, the i newspaper reported that the PM has a three-stage plan for exiting lockdown – which could include reopening pubs, restaurants and hotels from Easter weekend.
Meanwhile, Saturday's edition of The Daily Telegraph suggested that meeting a friend for a coffee on a park bench will be the first activities to be permitted if the lockdown eases on 8 March.
Johnson asked people to be “optimistic but also patient” about the situation, and said next week’s road map would set out “as much as we possibly can about the route to normality, even though some things are very uncertain”.
He said: “We want this lockdown to be the last. And we want progress to be cautious but also irreversible.
“I will be setting out as much of a timetable as we can give on the 22nd and I’m very hopeful that we will be able to go ahead and open things up.”
The government will analyse data this week on coronavirus case numbers, hospital admissions, deaths and the impact of the vaccine rollout as it prepares its plan to reduce restrictions.
According to the latest figures released on Monday, the UK’s COVID-19 infection rate is at its lowest since October, while the government reached its mid-February target of vaccinating 15 million people across the top four priority groups.
Johnson said there are “grounds for confidence” that vaccinations reduce the spread of coronavirus, but said the government is waiting for the “hard facts” before setting out the timetable for easing the lockdown.
At the weekend, more than 60 Conservative MPs from the COVID Recovery Group wrote a letter to the prime minister calling for the complete lifting of the lockdown by the end of April.
Watch: What you can and can't do during England's lockdown