Customers will receive the F-Secure software, which claims to prevent worms, viruses and spyware being downloaded, scans e-mails and comes with hourly updates and free technical support.

In another effort to cut fraud, the bank is also sending text messages to customers when a new payment is set up on their account.

Barclays spokesman Barnaby Davis said:

"Our new anti-virus and SMS text initiatives will go a long way towards offering customers additional protection and peace of mind, and help Barclays and its customers stay one step ahead of the criminals."