Make it compulsory for the PM to directly answers questions put at PMQs.

Background

The Speaker has said that he is not responsible for the answers given at PMQs I assume this is a Parliamentary rule), so why not change the rules to allow him to insist that the PM addresses the question asked?

Additional details

Too often, the PM ignores the question asked and launches into whatever he/she wants to talk about instead. It seems to be a Parliamentary rule that the Speaker cannot intervene in this. In fact, he said at PMQs on 18/3/26 that he was not responsible for the answers. I suggest the rule should be changed so that the Speaker is made arbiter of whether a question has been answered or not (matters of national security excepted).