asked Her Majesty’s Government:

Whether it is permissible for liquids purchased in a duty-free location and bottled in units of more than one litre to be carried in a passenger’s hand luggage when the passenger is in transit through a United Kingdom airport. [HL4712]

Under EU regulations, passengers transferring via EU hub airports (including those in the UK) are able to carry liquid duty-free items on to their connecting flight provided that the items have been purchased airside at an EU airport or on board an EU carrier, are supported by a receipt issued within the last 24 hours and remain in a sealed tamper-evident bag throughout the journey.