An Analogue of a Reductive Algebraic Monoid Whose Unit Group Is a Kac-Moody Group

By an easy generalization of the Tannaka-Krein reconstruction we associate to the category of admissible representations of the category ${mathcal O}$ of a Kac-Moody algebra, and its category of admissible duals, a monoid with a coordinate ring. The Kac-Moody group is the Zariski open dense unit group of this monoid.