Four million TalkTalk home phone customers will have more power to stop nuisance and scam calls, including those from overseas, after the firm launched a call blocking service.

The move comes as MPs demanded a crackdown on nuisance calls, recommending telecoms firms block numbers known to be making them (see our Stop Spam Calls and Stop Spam Texts guides for help).

Under TalkTalk's new service, customers who have had large numbers of calls from a single number can report them online. The firm will investigate complaints on a case-by-case basis, and will block numbers from its network if there is evidence of misconduct that breaks its rules.

The scheme is aimed at dealing with aggressive and persistent marketing calls, persistent silent or abandoned calls, or possible scams.

TalkTalk claims it's the first provider to allow customers to identify nuisance callers and block them at a network level.

But it says there will need to have been an "excessively high frequency" of calls in a week for a number to be blocked – including 10 calls a week for suspected scams, and 30 for sales calls. An expert team will also look for other signs of abuse, like the originator trying to hide their number.

A trial of the service found some companies were reported as calling customers over 65 times in a week.

TalkTalk's service is similar to the Telephone Preference Service (TPS), which allows customers with any UK provider to register their details on a central database for free. Once on this service, it's illegal for UK sales companies to contact you.

However the TPS can do little to deal with calls from overseas, whereas TalkTalk says it will block numbers from other countries, so long as they can be identified.

In April, TalkTalk itself was fined £750,000 after its sales teams breached Ofcom rules on silent and abandoned calls (see the TalkTalk fined MSE News story).

Public 'under siege' from nuisance calls

The move by TalkTalk came as a cross-party group of MPs called for a "step change" in efforts to tackle nuisance calls.

The All-Party Parliamentary Group on Nuisance Calls wants measures to improve enforcement, raise awareness and develop technology to stop unwanted sales calls.

It adds telecoms firms should be forced to block offending numbers, while industry regulator Ofcom could do more to help vulnerable customers who find themselves on a "suckers list" used by people running scams.

The group's co-chairman Mike Crockart says: "What became clear as the inquiry progressed was that we cannot wait a year or more for the Government to act.

"The public are under siege from nuisance calls and text messages and we need immediate action to protect consumers from scams, constant pestering and most especially undue influence on the vulnerable."

Additional reporting by the Press Association.