Travellers who try to fly during Covid lockdown face a £200 fine if they fail to complete a form setting out the reason for their trip, the Department for Transport (DfT) has said.
From Monday, people travelling internationally from England will need to complete and carry a Declaration to Travel document, downloaded from the government's website.
Failure to produce a completed form will be an offence and hopeful travellers could could face a £200 fine, the DfT said.
Staff will check forms have been completed before passengers are allowed to board, either at check in, or at the departure gate. Anyone without a completed form will be denied access to the flight.
Police, who have stepped up presence at airports in recent weeks to ensure compliance with Covid rules for arrivals to the UK, will have powers to request passengers produce a form and can issue £200 fines for failure to do so.
The new mandatory form has been announced after Cyprus said it would allow British tourists into the country from the beginning of May if they had been fully vaccinated, 17 days before the earliest point at which holidays abroad could be permitted.
Tourists will need to have had their second dose of a vaccine approved by the European Medicines Agency at the latest seven days before travel, Cyprus' deputy tourism minister Savvas Perdios said.
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However, in the roadmap out of lockdown for England, the earliest people will be able to travel abroad for holidays is May 17. The date is dependent on various factors, including the progress of the vaccine rollouts and the spread of Covid-19 variants.
Asked about the move by Cyprus, Downing Street said all flights outside the UK are currently banned under lockdown rules, other than for a limited number of exemptions.
Anyone wishing to arrive in the UK must have had a coronavirus test with a negative result with 72 hours of their flight.
People arriving from "red list" countries where coronavirus variants of concern have been identified will be required to quarantine in a hotel before they can enter society.
Number 10 said the Global Travel Taskforce has been tasked with developing a framework for international travel, which will help Boris Johnson determine when and how it can resume.
The taskforce will provide a report to the prime minister on April 12 to help him make a decision on the restart of international travel, which the roadmap out of lockdown says will happen on May 17 at the earliest.
The report will look at how existing measures, such as the test and isolate schemes, could be used to facilitate travel while managing the risk from imported cases and "variants of concern" - such as the recently imported Brazilian strain.
Transport Secretary Grant Shapps, who chairs the taskforce, said their job is to explore "safe and secure ways to restart international travel when the time is right".
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