In view of the terrorist alert on aircraft flying out of London, airlines that operate flights to and from London have changed baggage rules temporarily.

An Air-India public relations officer said no hand baggage -- what you can carry with you in the seat -- would be allowed in flights out of Heathrow airport.

"It is a British government instruction, which Air-India will follow," the official said, adding that for all Air-India flights out of India, hand baggage would be allowed as usual.

The no hand baggage rule is a must for all airlines flying out of London, he added.

For passengers taking an Air India flight out of London, "hand baggage will be checked in."

In a message on its web site, British Airways outlined an advisory by Britain's Department of Transport, which specifies what can be carried on aircraft flying out of London:

• Travel documents essential for the journey (eg passports, tickets and visas)
• Pocket sized wallets and pocket sized purses plus contents (for example money, credit cards and identity cards).
• Handbags are not permitted.
• Prescribed medicines essential for the duration of the flight, except in liquid form unless verified as authentic.
• Spectacles and sunglasses, without cases.
• Contact lenses, without bottles of solution
• For those traveling with an infant: baby food, milk and sanitary items essential for the flight.
• Keys (but no electrical key fobs).

Every other item must be carried in customer's hold luggage.

Though the advisory is for a 'limited period,' for aircraft flying out of London, it would be wise to call up your airline before you head out to catch that international flight.