Ashim Pal, a vice-president at Meta Group, said purchasers and their IT counterparts had been slow to set up a policy covering such devices, which are owned by a growing number of people.

"When faced with orders for phones from employees, purchasers should let senior management know there are security issues," he said.

"Many employees have them as part of their lifestyle now, but they can be misused around sensitive areas such as airports and major industrial and construction sites."

He said transmitting pictures and data on them was getting much easier, and images from sensitive sites could be useful to people outside the company.

One purchaser who buys phones for employees at a major UK airport said it had no policy on camera phones but it "could be something we look into".

Pal noted that phones increasingly have complex IT systems that are expensive to upgrade and may not be compatible with a company's other IT equipment. This means they lose value quickly as they can only be used for a short time.

A spokesperson for research organisation Qintec said it did not allow any mobile phones on company premises because they interfered with radio-wave sensitive equipment.