Does “pause” here refer to anybody at all? Should I interpret it as “there was a break/there was silence” or does it mean “Nikaberk paused for a long time”? 
“Well, Nikabrik,” he said, “we will hear your plan.”
There was a pause so long that the boys began to wonder if Nikabrik was ever going to begin; when he did, it was in a lower voice, as if he himself did not much like what he was saying.