New rules governing work benefits could see HM Revenue & Customs taxing employees hundreds pounds for sending too many emails via ever popular BlackBerry devices.

At present, HMRC will tax anything ‘designed to be used by being connected to or inserted into a computer’ including printers, scanners, modems and even MP3 players', The Times reported.

HMRC described the suggestions as 'complete nonsense' today.

BlackBerries and other 'personal digital assistants' (PDAs) had been exempt from tax because they were used mainly as mobile telephones, but because of the increasing sophistication they have drawn the interest of HMRC.

An updated version of HMRC’s employee benefits manual now says: ‘Technology has developed to such an extent that PDAs and BlackBerrys [sic] now have additional functions more typically associated with a computer.’

A spokesman for HMRC said: 'It is complete nonsense to suggest that the rules issued in August create additional reporting requirements on either employees or employers or that we will be engaging in some counting exercise of the number of e-mails an employee sends on their work computer or blackberry, completely absurd.

'The key point remains where equipment is provided with the sole purpose of enabling the employee to perform the duties of his or her employment, tax is not due provided that any private use of the computer is not significant

'If the equipment is necessary, it will be very unlikely that any private use made of that equipment would be significant when compared to the business need.'