A planned relaxation of rules around airline passengers carrying liquids in hand luggage has been delayed by a year.
Major UK airports are believed to have been granted an extension for installing the new scanning technology after they were unable to meet the 1 June deadline.
The 12-month extension was issued by the government on a case-by-case basis and is expected to be enough time for them all to complete the work.
The new scanners produce more detailed images, meaning passengers will be allowed to pass through airport security with containers holding up to two litres of liquid in their hand luggage.
A 100ml limit currently remains in place in airports that do not have the technology, and containers must be put in clear plastic bags.
The new scanners also end the need for laptops and tablets to be removed from hand luggage.
Many airports have struggled to install the new equipment ahead of the busy summer holiday period, largely due to supply chain delays and construction difficulties caused by the weight of the machines.
It is not the first time the change has been pushed back after it was originally set to come into force in December 2022, by former prime minister Boris Johnson.
It was later pushed back to June this year after the aviation industry suffered huge disruption due to coronavirus travel restrictions.
The government has now said that financial penalties could be imposed for further non-compliance after the extension runs out.
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Despite the delay, the Department for Transport said half of passengers flying from UK airports will be processed by the new scanners by the start of June.
It refused to provide a breakdown of the situation for each airport, citing security concerns.
London Heathrow has previously said it expects to have new scanners in all security lanes this summer, and it is unknown if the UK’s busiest airport is affected by the delay.
Meanwhile, London Gatwick expects to complete the programme by the end of March 2025.
Manchester Airports Group – which runs Manchester, East Midlands and Stansted airports – also said its scanners will be fully rolled out next year.
In April last year, London City became the UK’s first major airport to begin using the new scanners for all passengers.
Transport Secretary Mark Harper advised passengers to check with the individual airport before travelling.
He said the UK is “leading the world” with the rollout of the technology and airports must be given a second chance to “get the job done”.
Karen Dee, chief executive of trade body the Airport Operators Association, added: “As with any programme of this complexity, there are significant challenges, and we are happy the government has recognised these and agreed to extend timeframes for delivery where necessary.”
Airport security restrictions for liquids were first introduced in 2006 following a foiled terror plot to blow up planes flying from London to the US with homemade liquid bombs.