Brussels, Belgium ? European Union air safety officials on Wednesday backed tightened rules on the amount of liquids and size of carry-on baggage that passengers can bring onto commercial flights – even as the U.S. has eased its restrictions.

The stricter EU-wide security rules are a response to Britain’s discovery on Aug. 10 of a plot to bring down U.S.-bound flights with liquid-based explosives.

The European Commission said its tighter limits on liquids will enter into force in early November. The rules would let passengers carry on no more than a fifth of a pint of liquid per container. All such containers will have to be in a clear plastic bag to be checked at security stations.

The rules also limit carry-on baggage to a maximum of 22 inches by 17 inches by 10 inches – not much bigger than a briefcase or laptop bag – although exceptions could be made for some items such as musical instruments.