Broadband providers Tiscali and BT have entered into a row which has stemmed from BT's apparent targeting of its rival firm's customers.
Reports suggest a letter was sent to customers of Tiscali and Phoenix under the heading 'Tiscali chief plots sell-off', inviting customers to switch broadband company.
Questions have been asked as to how BT Retail managed to acquire the details of Tiscali customers and Tiscali has threatened to take legal action.
According to PC Pro, the letter reads: "We can understand why you're wondering what might happen to your Tiscali broadband service.
"And because no one really knows the answer just yet, it could be a good time to look for an alternative broadband service."
Tiscali has moved to dismiss reports that it is to be sold by the middle of next month.