Queues are expected at European airports this summer due to the EU's new digital border control system. This was reported by Qazaqyia.kz citing BBC News.
It is the first summer peak period since the Entry/Exit System (EES) came in. It requires UK travellers to register fingerprints and a photo alongside a passport scan.
EES will replace the manual stamping of passports. It tracks who enters and leaves the Schengen free movement zone, which covers 29 European countries.
"Third country" nationals - including UK citizens - must provide fingerprints and a photo at passport control. Brits flying out to popular holiday destinations including France, Spain, Portugal and Italy will be required to do this at automated kiosks after they land. The information is verified when they leave.
Some passengers, including children under 12, have their passport checked by border staff instead.
EES started to be rolled out in October last year and is now fully up and running. The time it takes to register biometric information means people have been told to prepare for a wait at border controls.
During the introductory period, queues started to flare up at certain airports at busy times. Since then, the system has been working well in some airports, while waits of several hours have been reported at others.
A representative of airline trade body IATA has warned queues in some places could be as long as six hours. Travel experts and industry figures have blamed problems with the technology and border staffing levels. There have also been reports of people having to register their biometric information more than once.
The UK boss of Wizz Air told the BBC passengers should be prepared for a wait, and turn up three hours before their flight home. Some passengers have missed flights home because the wait for EES checks meant they could not reach their gate in time.
Whether airlines will hold flights for passengers who get held up is a mixed picture. Some say they will wait wherever possible, while Ryanair is an example of a carrier which has said it will not.
The summer holidays will provide a major test of the new system. Greece is not applying the biometric checks to British visitors over the peak period. The European Commission is allowing the system to be suspended in "exceptional circumstances that lead to excessive waiting times", until September.
Improvements are planned in some places which have seen the worst queues. For example, Portugal has announced hundreds of extra border staff for July. Airports say passengers should follow the advice of their airline when it comes to how early to arrive for flights back to the UK.
At a few locations, French border police conduct passport checks before people leave the UK. They are Dover's ferry port, Eurotunnel's Folkestone terminal, and Eurostar's St Pancras rail terminus.