I will be flying from Heathrow to the Canary Islands later in the year. I've booked with Iberia and change planes in Madrid. Are the rules for taking liquids on a plane out of Madrid the same as here? Peter Reynolds, Hereford

Sunday Times travel expert Richard Green responds: There was an awkward period after the new limits on carrying liquids in aircraft cabin were introduced, when the rules differed from one country to another. Thankfully though, the common policy has now been adopted by all EU member states ­ plus Switzerland, Norway and Iceland.

So wherever you board a plane in the European Union, you can only take liquids past the security search point if they are in containers not exceeding a capacity when full of 100 ml. And they have to be placed in a closed transparent and re-sealable bag that has a capacity not exceeding 1 litre (about the size of a small freezer bag).

If you are in transit and don't clear customs, it is fine to carry liquids in excess of the limits, providing that you purchased them in the departure lounge, or onboard the aircraft, on your inbound flight.

Essential medicines are an exception, and you can take enough supply for the duration of the trip ­ the trip here meaning the length of your holiday, rather than just the flight - providing that you can prove that they are essential. A letter from your doctor will suffice. You should mention this to your airline when you book, or at least 24 hours before you fly.

As a reminder, "liquids" here includes all drinks, water, soup, syrups, creams, lotions, oils, perfumes, mascara, sprays and pressurized containers (including shaving foam and spray deodorants), toothpaste, and gel.

Liquid baby food or sterilized water, sufficient for the length of the flight, can also be taken through airport security. The accompanying adult will be required to prove this by tasting it at security.

For a guide on the rules, see the latest Government guidelines

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