ex boyfriends clothes?

I broke up with my ex boyfriend approximately 3 months ago and I'm completely over him and have no desire to come face to face and talk to him. I have his clothes in a bag for a while and I feel like some are important so I would like him to return them back.. how should I approach this? He said he doesn't want it but I really don't feel comfortable donating it cause there's some important stuff I think he will regret later so.. any advice?