This is from the American Airlines site...
Updated Baggage Policy Information
Information is current as of 9:00 a.m. (CST) August 10
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Travel Policy For UK Carry-On Bagggage
..... all cabin baggage must be processed as checked baggage and carried in the cargo hold of all passenger aircraft departing from or connecting through airports in the United Kingdom (UK). This policy also applies to any aircraft departing the United States traveling to the UK.
The following measures apply to all passengers starting their journey at a UK airport and to those transferring between flights at a UK airport and from anywhere connecting in the US to the UK.
Nothing may be carried in passengers' pockets... (EXCEPT) ... the following items through the airport security checkpoint, in a single (ideally transparent) plastic carrier bag:
pocket size wallets and pocket size purses plus contents (money, credit cards, identity cards, etc. but not handbags)
travel documents essential for the journey (passports and travel tickets)
prescription medicines and medical items sufficient and essential for the flight (a diabetic kit for example), except in liquid form unless verified as authentic. spectacles and sunglasses, without cases
contact lens holders, without bottles of solution
for those travelling with an infant: baby food, milk (the contents of each bottle must be tasted by the accompanying passenger) and sanitary items sufficient and essential for the flight (wipes, creams, disposal bags) female sanitary items sufficient and essential for the flight, if unboxed tissues (unboxed) and/or handkerchiefs
keys (but no electrical key fobs) There will be no liquids or gels allowed to/from the UK. Duty free from the UK will not be allowed, however, duty free onboard will continue.
All UK transiting passengers will be required to check any carry-ons they bring to the airport regardless of origination. For passengers who have already left the US and will be connecting in the UK, they will not be allowed to use the transit area in the UK airports and will be routed back to the ticket counters to check their carry-on luggage.
For the customers affected by this new policy, we will waive excess baggage fees for customers who arrive at the airport for connections in the UK or who are departing from the UK and must now check their carry-on baggage.
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