Let's talk soon.

"Let's talk soon" actually means just the opposite. It's a way to end a conversation with someone, usually someone you haven't talked to or seen in a while, without appearing rude. When someone says this, they probably have no real intention of talking to you soon, and it could be a while before you hear from them again.

Example:
-It sure was nice seeing you again!
-It sure was! Let's talk soon!