With hundreds of thousands of holidaymakers nervously hanging on his every word, it is fair to expect the transport secretary to have a firm grasp of the details when announcing France would be removed from the UK’s travel corridor list. But Grant Shapps sowed confusion on Thursday night by apparently giving out the wrong information, suggesting the quarantine measures would be coming into force on Sunday when, in fact, they are doing so 20 hours earlier. Shapps said during a TV interview that people arriving in the UK from France would have to isolate for 14 days from Sunday, but the move is actually coming into force at 4am on Saturday. Meanwhile, in a swiftly deleted tweet referencing the imposition of the measures, Shapps declared at 10.45pm on Thursday: “It’s Saturday at 4am, meaning that anyone returning on Sunday onwards will need to quarantine.” The Guardian has been told some holidaymakers mistakenly booked return trips later on Saturday after seeing Shapps’s interview, meaning they would arrive after the measures came into effect. During the TV interview, Shapps said: “Well, the French government have said that unfortunately the virus has been going the wrong way there. “There’s been a 66% increase in the number of positive tests in the last week alone. And so, unfortunately, France is having to be added to the quarantine list. That means if you’re coming back from France then you must self-isolate for 14 days when you come back from Sunday.” The measures also apply to people arriving from, among other countries, the Netherlands, Malta, the Turks and Caicos Islands, Aruba and Monaco. The broadcaster Andrew Neil, whose tweet to Shapps asking about the timing of the measures prompted the now deleted tweet, was characteristically unsparing in his criticism. Neil wrote on Twitter: “I fear the transport minister didn’t know what he was talking about.” In another tweet, Neil said: “Transport minister Shapps has just deleted his tweet to me. I suspect he thought 4am Saturday was early Sunday morning. It’s not. It’s 4am Saturday.” One woman told the Guardian on Friday that her brother-in-law and family were staying with her in France and were due to leave on Monday but, after seeing Shapps’s TV interview, quickly paid £230 to book a Eurotunnel ticket for Saturday afternoon. Amanda Hill said: “They were of course shocked to wake up to find out the quarantine starts from 4am tomorrow morning. “They are of course extremely upset and angry and now have to quarantine with six-year-old twins. Why hasn’t he acknowledged his mistake and the impact it has had?” A Department for Transport source said on Friday: “During his recorded interview straight after the decision on France was taken he made a slight slip which may have confused people about timings. “The last thing he would want to do is cause confusion for people in France dealing with this difficult situation.” In an additional comment, a DfT source sought to point the finger at Sky News by claiming Shapps realised the “possible confusion” caused by his comments and requested for that part of the clip not to be broadcast. The source said: “The comment on the timing of quarantine coming into effect was made during a pre-recorded pool interview with a Sky camera team. The secretary of state recognised the possible confusion and asked that the timing comment not be used in the broadcast clip. But this comment did appear on air temporarily.” Sky News has been contacted for comment.