Passengers will be able to carry liquids and laptops through security at London's Heathrow Airport inside their hand luggage after new security scanners are installed.

Heathrow is investing more than $63 million in new equipment that can better see inside closed bags.

"Passengers could soon keep their liquids and laptops inside their cabin baggage when passing through security at Heathrow," the airport said in a statement.

Heathrow said the more efficient system would reduce the time that passengers spend in security, and would also cut plastic use by eliminating the small bags passengers currently have to stuff their cosmetics into.

The airport has been trialing the technology since 2017. The airport says it expects the scanners to be rolled out across its 5 terminals by 2022.

The scanners use the same technology as CT scanners in hospitals, which can see through the body to analyze internal organs and bones.