Alberta's referendum campaign entered its final week with a prominent former premier questioning why a U.S. billionaire is weighing in at all.

Rachel Notley told CBC's Rosemary Barton she has concerns about Elon Musk's public support for Alberta separatists and about U.S. involvement in the debate, and she suggested Premier Danielle Smith's actions have encouraged separatist voices. Smith has said she wants a more autonomous Alberta inside a united Canada while arguing separatists' grievances deserve a hearing.

The exchange came on a Sunday political panel that also dealt with criticism of Ottawa's Bill C-39, which would expand the federal government's power to fast-track major projects. A B.C. Liberal MP said he supports the bill but wants appropriate safeguards as it moves forward.

Voting day is October 19. The referendum will not by itself separate Alberta, but a strong separatist showing would open the door to a binding vote and prolong a national-unity fight that has already drawn in the prime minister, who is expected in Alberta this week.