When I first heard the phrase ‘touch base’ years ago, I had absolutely no idea what it meant. A girlfriend wanted to ‘touch base’ with me. I’ve heard it many times since then, and so it’s no longer new to me.
‘To touch base’ means ‘to make contact’ or ‘to talk to someone in order to find out how they are or what they think about something’. The term comes from baseball, as far as I know.
It’s a term that I wouldn’t use in international business. I’d rather say, “I’d love to get together with you and talk about …”.