The club has been given permission by the league to train the refugee.
The move was made after intervention by Oleksandr.
At youth level, the pair played together.
When the Russian invasion of Ukraine began, he was on a training camp in Turkey.
He will train with the Under-23 squad for the rest of the season after he left his contract and fled to Manchester.
I felt really uncomfortable when I was playing for a Russian club.
I was playing in a country that invaded my homeland. The only decision was to leave the club. If I continued to play there, people would not understand me.
His brother is fighting in the country's armed forces and his family is in Kyiv.
I tell him every day how proud I am of him for protecting our family and the country. He is staying and fighting.
I am really worried. I receive bombing alert messages on my phone. I am so anxious when those notifications come through. Your only thought is that my family will die.
He said he was so grateful to Manchester City for allowing him to train there and to his countrymen for help in finding a solution.
The past few weeks and months have been difficult, but to be back on the pitch means a lot to him.
He wished the circumstances were different, but it was good to be back with Andrii.
I know how much football means to him and how it can help us during difficult times.
Earlier this month, the Premier League blocked Burnley's bid for Victor Moses from Spartak Moscow despite Fifa amending their rules to allow overseas players in the Russian Premier League to sign for clubs in other countries outside the transfer window.
They have agreed to let him join City so he can maintain his fitness and continue his development.