How to invite Party A’s Chairman by phone if Party B invites Party A’s Chairman to dinner?

After the call is connected, first say hello to the leader and explain who you are. Then the leader will be free, and then talk about dinner.

After the call is connected, first say hello to the leader, explain who you are, and then ask if the leader is free at what time. Then, depending on whether it is appropriate to directly say that you want to invite the leader to dinner, you should directly say that you want to invite him to dinner. The meaning is expressed tactfully, that is, you have to think carefully about the reason for your invitation to dinner.