Internet service providers (ISP) will have to give greater clarity over their broadband speeds under a new code announced by media regulator Ofcom on Thursday.

Ofcom said it had decided to act after seeing consumer satisfaction in ISPs fall in the last year.

Under the code, service providers will have to provide customers with an accurate estimate of the maximum speed that the line can support.

Internet service providers advertise broadband speeds as being up to a certain megabyte, but the speed drops the further a customer lives from the exchange and Ofcom has voiced concern about the discrepancy before.

The regulator said some 32 ISPs, covering over 90 percent of broadband customers, had signed up to the code including AOL, BT , O2, Sky, TalkTalk and Virgin Media.

ISPs will also have to offer customers the choice to move onto a lower speed package when the estimates are inaccurate.

Ofcom will also launch a programme of independent research.

The Internet Services Providers' Association (ISPA) welcomed the move and urged Ofcom to extend the code to mobile broadband providers.