Yes it's a normal thread on this side of the crank, not the opposite thread like the other side of the crank.
Stand the chainring vertically on a hard surface (on a pile of rags if you need to keep the chainring) and hit the side that needs to go downwards towards the ground. You need to shock it off to undo it if it's old as it's designed to tighten up when pedalling.
If it won't move, try release oil like plusgas or something, or petrol to remove the grease then deisel to creep into the gaps, then hit it again.
Finally, use a chisel and a 3-1/2 lb club hammer and it will shift eventually.