And the Daily Star says the confusion over foreign holidays is igniting a boom for camping holidays in the UK.
This led to an angry reaction from the travel industry.
Heathrow Airport chief executive John Holland-Kaye said it is "disappointing that the opportunity has been missed to provide more certainty to reunite families separated by travel restrictions, to give sunseekers the confidence to book ahead for their summer getaway and to help businesses across the country that have had their exporting ambitions placed on hold by the pandemic".
Airport Operators Association chief executive Karen Dee said she was "disappointed" the update "continues to suggest significant barriers to global travel, and may push back the date of restart beyond May 17".
Under England's road map for easing pandemic rules, the earliest that foreign holidays could be permitted is May 17.
"As we continue to make good progress on our vaccine program and with our roadmap to cautiously easing restrictions under way, regular rapid testing is even more important to make sure those efforts are not wasted", Johnson said in a statement.
"Obviously we are hopeful that we can get going from May 17th, but I do not wish to give hostages to fortune or to underestimate the difficulties that we are seeing in some of the destination countries that people might want to go to", Johnson told a news conference, adding that he did not want to see cases being reimported into Britain. "We can see the waves of sickness afflicting other countries, and we've seen how this story goes".
The global travel taskforce review warned "the state of the pandemic overseas, and the progress of vaccination programmes in other countries" meant it was impossible to say yet whether foreign holidays would be allowed from 17 May, the date earmarked as the earliest possible for the resumption of worldwide trips.
"We still don't know how strong the vaccine shield will be when cases begin to rise, as I'm afraid that they will, and that's why we are saying please get your vaccine - or your second dose - when your turn comes".
On the traffic light system, Dooey said: "This system has to have clarity and we all need to know the data which will trigger the move from one category to another".
"These decisions will be driven by the data and evidence nearer the time, which we can not predict now".
It confirmed that the government is examining a traffic-light system for countries, with travel to green list nations requiring no quarantine on return to the United Kingdom - although tests will still be required - although it is too early to say which destinations will be in that category. People returning from green countries would not have to self-isolate. Countries on the amber list would require self-isolation.
The document stated it is "too early to say" which countries will be on the green list.
It added: "For the moment, the Government advises people not to book summer holidays overseas until the picture is clearer". In parts of Wales where 111 isn't available, call NHS Direct on 0845 46 47. Only call NHS 111 if you can not cope with your symptoms at home; your condition gets worse; or your symptoms do not get better after seven days.