Cold callers will be made to display their phone numbers under new rules intended to crack down on nuisance calls.
Under the new rules direct marketing companies must display their numbers so that those they call are able to block them or report them to the information commissioner.
The rules apply even when the company's call centres are based abroad.
"This [legislation] means the consumer can actually see for themselves and help to stop the calls, and help us with the policing," Baroness Neville Rolfe, minister responsible for data protection, told ITV News.
- Baroness Neville Rolfe speaks to ITV News:
The new rules, which come into place on Monday, will also mean nuisance callers face stronger penalties and investigation by the the information commissioner's office (ICO).
Baroness Neville Rolfe said: "Nuisance calls are incredibly intrusive and can cause significant harm to elderly and vulnerable members of society.
Steve Eckersley, the ICO's head of enforcement, welcomed the move saying it would help his office better investigate complaints.
"Any change that make it easier for us to track down and take action against companies making nuisance calls is a change that will reduce the annoyance these calls cause," he said.
"We do investigate unscrupulous companies who hide their identities, and we can track them down, but it certainly makes our job more difficult."
Companies that make nuisance calls risk fines of up to £2 million, and could face a further £500,000 fine from ICO if they continue to bombard consumers with unwanted calls.