Firebellies are pretty aggressive breeders. I never knew what intense breeders they were since I started following this thread:
http://www.frogforum.net/showthread....na-have-babies

I think elly is right, separating them for a while is probably your best option. Based on what I've read in Alane's thread I lInked above, they'll probably just keep trying if you don't lol.