Mendicino says the federal government is ``looking at a variety of options'' to carry out a planned buyback of banned firearms -- including enlisting outside help.

In an interview with The Canadian Press, Trudeau also defended his government's intention to allow handgun prohibition on a city-by-city basis rather than enacting a sweeping federal ban.

The bill also forces gun retailers to keep records of firearms inventory and sales and requires the purchaser of a hunting rifle or shotgun to present a firearms licence, while the seller will have to ensure its validity.