SCOTT JAGOW: The airlines are in a precarious situation with these new security measures. On one hand, they have to make sure their planes are safe. On the other hand, people might not tolerate too much inconvenience. Today in Britain, officials are meeting to talk about how long this should go on. Stephen Beard has more from London.

STEPHEN BEARD: The heightened security, the long delays and the flight cancellations have already cost the major airlines a fortune.

Yesterday alone they're estimated to have lost more than $20 million between them.

The worry now is how long the ban on hand luggage will continue. That could damage business travel, the most lucrative market for transatlantic carriers.

Analyst Kierean Daly says business travelers will not be parted from their laptops.

KIEREAN DALY: We've already been talking to business travelers who are saying it's simply not realistic for me to go around the world without working on my laptop in flight. I can't take 12 or 14 hours out of my day and still justify that amount of travel.

Also he says they don't want to consign their precious laptops to the rough and tumble of the cargo hold.

If business people fly less and do more videoconferencing, he says, airline profits will collapse.

In London, this is Stephen Beard for Marketplace.