"What we have discussed in the past or will in the future is not a matter that concerns him." By nature he is a private person- it played a large role and aided in Lara's pregnancy not being discovered- and even in the eventuality that Kal-El asked, he would not undertake the task.

"I don't believe you have any current interest in attempting to hurt him for the time being. I will not ask you where the Kryptonite is or for you to give it to me, but you must understand that it is not dangerous for only Kryptonians." Kal-El had informed him of that, the first time he mentioned the substance and its dangers. "You need to make sure that it is properly contained."