Cheerful,
Sweetheart, if you like the guy generally as a friend, you can tell him that.
Otherwise do whatever you wish.
But it seems like you had a decent conversation on the phone.
I dated a guy like this and I told him straight up why I was repelled by him. Can you believe he lost weight just because I said he was obese!
Also, the next time I saw him, he was very handsome and very thin. Too bad I screwed that relationship up, he was a millionare...