Jacinda Ardern says she'd want to see evidence of a gun buying spree, before issuing a moratorium on imports and sales

Cabinet will today begin discussing the firearms law changes the Prime Minister has promised in the wake of the Christchurch terror attack.

There have been calls for an immediate moratorium while changes are in process, following anecdotal reports of a run on gun purchases.

But Ardern says she'd want to confirm whether that's the case first.