A Senate committee has voted to amend the federal government's cannabis legalization bill to allow provinces and territories to ban home-grown marijuana.
But it has refused to accept an amendment that would have prohibited home cultivation outright.
Bill C-45 would allow individuals to grow up to five plants in a single dwelling.
But Quebec and Manitoba have decided to prohibit home cultivation, setting up future legal challenges in which Justice Minister Jody Wilson-Raybould has said the federal legislation would prevail.
The Senate's social affairs committee, which is conducting a clause-by-clause examination of the bill, has unanimously supported an amendment specifying that provincial and territorial governments have the authority to prohibit home-grown pot if they so choose.
But another amendment proposed by Conservative Sen. Judith Seidman that would have imposed a blanket prohibition on home growing across the country was rejected by a vote of 7-5.