The CRTC has warned the Conservative Party of Canada it is not doing enough when it comes to maintaining its internal do not call phone list. (CBC)

Canada's telecom watchdog says the Conservative party has fallen short when it comes to its do-not-call list.

The CRTC's chief compliance and enforcement officer expressed her concern in a letter to Conservative party executive director Dan Hilton.

Andrea Rosen says the CRTC has launched an investigation prompted by a recent complaint about how the party handles internal do-not-call requests.

Political parties are exempt from the national do-not-call list, but they still have to keep an internal list and respect the wishes of people who tell them they don't want to be contacted.

The Conservative party keeps two internal do-not-call lists: one for solicitation purposes and another for outreach or voter identification.

Rosen says keeping two lists has created some confusion, and the CRTC has asked the party to keep a single list and respect the people's wishes to not be called.

The CRTC has also asked the Conservatives to make sure all scripts used on calls are clear, and that third-party telemarketing firms follow all the same rules.

Conservative party spokesman Fred Delorey says changes were made once the CRTC raised the issue. He noted the party has not been fined or faced any sanctions over what he called an "administrative issue."

"Unlike the Liberals who were fined nearly $5,000 by CRTC for placing misleading robocalls, this was simply an administrative issue with our live calling," he said in an email.

The CRTC recently hit the federal Liberal riding association in Guelph, Ont., with a $4,900 fine for robocalls that broke the rules during last year's election campaign.

The CRTC said a recorded message that went out to voters on Apr. 30, 2011, violated telemarketing rules by failing to state that it came from the Liberal party or MP Frank Valeriote's campaign.

That CRTC fine pertained only to a breach of telemarketing rules and not to any possible violation of the Canada Elections Act.