Telecoms regulator will use its "full range of powers" to stop unwanted phone calls to UK landline customers.
Ofcom has renewed its promise to clamp down on nuisance calls to home phone lines.
In a recent study, the telecoms regulator measured the number, type and frequency of unwanted phone calls to UK landline customers.
Nuisance calls were received by 82% of participants in the four-week study, and over a quarter had more than 10 unwanted calls during that time. On average, home phone customers get around two nuisance calls per week.
The most common offenders were 'cold calling' salespeople (38%), silent calls (34%) and pre-recorded sales messages (14%).
Ofcom said it would use the "full extent" of its legal power to stop the problem for good.
Claudio Pollack, Ofcom's consumer group director, said: "Two nuisance calls a week is too many and this detailed research will help us understand the root cause of the problem.
"We will use the full range of our powers ... but this is a complex area that requires joint action from a number of different agencies and government.
"We are therefore working with the government and other regulators to help drive a coordinated and more effective response."
Most of the nuisance calls were related to payment protection insurance (PPI), accounting for 22% of all unwanted phone calls received during the study.
Energy firms (10%), market research (10%) and insurance sales (8%) were also among the most common types of nuisance call.
In February, BT launched a phone that can be programmed to block unwanted calls.
The BT6500 home phone gives users the option of blocking up to 80% of nuisance calls - from international, withheld or specifically chosen numbers. Blocked calls are sent to a built-in answer machine, where genuine callers can then leave a message.