Ofcom says it is working hard to reduce the "growing problem" of nuisance calls - but has called for more action.
It wants current regulations to be reviewed, and says it is working on ways of tackling the "root causes" of nuisance calls, which it will share with the UK Government.
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 to tackle abandoned and silent calls, 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 to nuisance calls.
Ofcom has announced it is investigating suspected abandoned and silent calls made by claims management companies, "using the full extent of its legal powers."
In January, it published a five-point action plan for tackling the problem - including trying to better trace the companies behind nuisance calls, and better enforcement.
TalkTalk was fined £750,000 last month for making an excessive number of abandoned and silent calls.
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