Bradford firms were today warned to be on their guard against unsolicited "invoices" for entry in an international business directory.

Firms in the region, as well as the West Yorkshire Trading Standards' own accounts department, have received "invoices" from a company called United Telecom International Trade and Business Database of the Czech Republic.

The invoice states that, for £354.05, West Yorkshire Trading Standards Service can have an entry on an Internet and CD-ROM fax directory.

Councillor Malcolm Slater, chairman of West Yorkshire Joint Services, which oversees the work of Trading Standards, said: "Businesses need to be extra vigilant: these look like genuine invoices.

"It was lucky that eagle-eyed staff at Trading Standards spotted it, but this "bill" could easily have been paid.

"If these documents had originated in the UK they would have to be clearly marked with indications that they were not demands for payment and that there was no obligation to pay.

"As they originate from overseas it is difficult to stop them and recipient companies can be misled into believing they are bills and pay them.

"Under no circumstances should businesses respond to the mailshot. They should just bin it."

Further information is available by calling the consumer helpline on (0113) 3848848.