OTTAWA -- The federal regulator of Canada's telephone industry says it is giving service providers one year to implement a new measure that's designed to reduce the number of nuisance calls that get through to consumers.

The Canadian Radio-television and Telecommunications Commission says that by Dec. 19, 2019, the communications service providers must be able to block numbers that are blatantly illegitimate (such as 000-000-0000) or that exceed 15 digits.

It's the CRTC's latest attempt to deal with the perennial problem of unwanted calls.

A national do-not-call list that's been in place about a decade does allow consumers to register their numbers and file complaints, but it's not automatic and there are numerous ways to get around the system.

The CRTC said it views network-level call blocking to be part of a multi-prong approach to deal with nuisance calls, despite industry concerns that some legitimate communications could be blocked inadvertently.

The commission says that carriers won't have to provide network-level blocking if they offer more advanced call-filtering services, an option preferred by many of Canada's largest phone, cable and internet service providers.