The Argentinean striker has been subject to speculation for months after Pep Guardiola picked Brazilian youngster Gabriel Jesus ahead of him following his January arrival.
It appears those talks have gone well and Aguero will be staying at City for at least another season.
"Absolutely there was never any doubt about that", he said about the possibility of Aguero leaving. I think it's something which is important, it's critical, and I know it requires a lot of hard work, particularly in this league, to be in the top four, but our ambition is to win the league.More news: Trump's First G7 Summit Gets Down To Work In Sicily
"He is one of the best players in the world".
'It has never been in doubt'.
"There's never been a doubt about that". But an expected influx of up to six players does not mean that Agüero will be forced out of the club, according to the chairman. "Probably if I look back at this season that puzzle wasn't complete and I hope this summer we support Pep in competing that puzzle".
"In normal circumstances, ending the season without a trophy would be a very disappointing season - but it's not, it really isn't", he said.More news: Makarova stuns top seed Kerber in French Open 1st round
City fans will be delighted to hear Aguero will be staying as part of a lethal attacking unit next season.
Al-Mubarak admits the club will embark on another massive spending spree to land some of the world's biggest stars for Guardiola.
"I think the transition of this squad in this cycle started past year".
"This year has been another year in which he has shown us on the pitch the type of player he is, the type of personality he is, and how he continues to be a player who can give to the is team and to our organisation".More news: Back on court after knife attack, Kvitova wins in Paris
"(Manchester City owner) Sheikh Mansour asks for regular updates on how our thinking is evolving so there are no surprises by the time I come with the final list of recommendations.