Air travellers passing through London's Heathrow Airport have been warned that they will no longer be permitted to carry over-sized hand luggage, including some notebook computer bags.

The airport will be placing gauges at check-in desks for the new rule, which comes into effect on August 1.

Under the new rules, bags must be no more than 56cm long, 45cm wide and 25cm deep. Larger items will need to be checked in.

A British Airport Authority spokesperson said: "Passengers are now packing larger, thicker hand baggage filled with more electronic devices than ever before.

The move is to reduce the waiting time for security checks.

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