The government is under growing pressure to announce details of its quarantine plans, after hotels revealed no discussions had taken place.
Boris Johnson confirmed in January UK residents returning from Covid hotspots would have to quarantine in hotels.
But a timetable for the new measure has still not been confirmed, with Labour saying the plans are in "chaos".
The PM had said there would be an announcement on Thursday, but No 10 later said he had been "misinformed".
Home Secretary Priti Patel had also told the Commons that more detail would be provided to MPs this week.
But Mr Johnson's official spokesman confirmed the announcement would not come until next week.
Health Secretary Matt Hancock insisted there wasn't a delay to bringing in the hotel quarantine policy, adding that "what there is, is work to make sure that the border is always as secure as it needs to be".
Mr Hancock said the government was working "at pace" adding: "It's important to get it right."
Labour leader Sir Keir Starmer - who wants everyone coming into the UK from any country to be quarantined, with exceptions for transporting food and medicines - said he was "really worried about the chaos and confusion on the government's borders policy".
He warned the risk was "huge" if the UK did not secure its borders, saying we could "go back to square one" if a new variant that was immune to the vaccine got through.
Sir Keir added: "We're in a race now - virus against vaccination. Let's secure our borders."
'Yet to hear details'
Demands to introduce tougher border restrictions in the UK have been growing since the emergence of new coronavirus variants from other countries, such as South Africa.
Transport Secretary Grant Shapps introduced the requirement for travellers to have a negative test result before arriving in the UK last month, but critics continued to call for mandatory quarantine in hotels for all arrivals - echoing similar moves in Australia and New Zealand.
At the end of January, Mr Johnson confirmed this rule would be introduced, but only for UK nationals and residents returning from 30 "red list" Covid hotspots.
However, hotel industry leaders said on Thursday they are "yet to hear details" of government plans.
Speaking to BBC Radio 4's Today programme, the boss of Best Western, which has 250 hotels in the UK, said beyond "very broad information" about timings, hoteliers had not had "any discussions at all" with government.
Rob Paterson added: "In any normal company, if you went out and announced a programme nationally and you hadn't thought about how you were going to plan that, and you hadn't spoken to the people involved… I'm not sure I'd have a job if I did that in my company."
He said his industry "needed some assurance of what demand levels are going to be", as well as clarification on "security protocols".
Chief Executive of industry body UK Hospitality, Kate Nicholls, said: "Hotels have offered their help to the government, but we are yet to hear any details on the scheme.
"We are ready to provide assistance as and when hotels will be needed."
The Immigration Services Union - which represents workers for the UK Border Force - also claimed "nothing has been communicated" to them or staff.
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