He stops and turns to look at her. His scar is stark against his face. He holds up a hand. "Katara, we can't." He's not the political powerhouse some are, but he is savvy enough to know that him disrobing in front of his now betrothed is not a good idea. "It's unseemly."

He sighs and walks over to her. "I know you want to help. I wouldn't mind, but it wouldn't look good, and my position is tenuous enough, even with Aang's approval." He knows that too. Sure, there are a lot of people who want him to be Firelord, but Zuko is not convinced that he's cleared his advisors of his father's cronies. "Trust me, please." She needs to trust him in this, to know that he knows the politics around the palace complex.