The Metal Gear Solid creator told followers on Twitter that the project will be shown in full at Tokyo Game Show later this year.
"Typhoon 4. It looks like it won't have an effect on the weekend. Thank goodness! However, my health is bad. Prior to TGS, we'll have a big announcement on Saturday or Sunday, so I must recover," he said (via Andriasang).
He later added that it will not be Zone Of The Enders-related, saying: "ZOE3 and so forth - it's not that big an announcement. However, I think you will be happy."
Kojima was last reported to be working on a "massive PS3 exclusive".