Potty training and number two's?

we've just become a bit tougher with toilet training and my 2 1/2 year old, he usually goes around with no nappy because he doesn't like peeing on the floor and will tell me usually if he needs the toilet, this is the first time he's had to do a poo though, usually he'll go in the pull-up he wears for his nap or first thing in the morning before I take the one he had during the night off. he keeps grabbing his butt and asking to go to the toilet but he's not doing anything, he's asking to go every couple of minutes for almost an hour with no result, should I persist with taking him or just put a nappy on him?