He stated this during a speech at the Lowy Institute in Australia.
Gates said that prior to the conflict in Ukraine, the Ukrainian government was one of the worst in the world, corrupt and controlled by "a few rich people."
The Microsoft founder added that it was very sad for the Ukrainian people.
He expressed the hope that after the end of hostilities, the restoration of Ukraine will begin and it will reach "the level of European countries."
Earlier, Gates spoke about the negative impact of arms supplies to Ukraine on aid to African countries.