Sheikh Mansour bin Zayed al Nahyan promised on Tuesday that he and his Abu Dhabi United Group were at Manchester City for the long term after completing the negotiations for their takeover of the Premier League club.

"I am delighted to tell you that negotiations are complete and the transfer of ownership will take place on Tuesday September 23," Sheikh Mansour said on the club's website (www.mcfc.co.uk).

"We are ambitious for the club, like you, but not unreasonably so and we understand it takes time to build a team capable of sustaining a presence in the top four of the Premier League and winning European honours.

• Images: Manchester City thrash Portsmouth 6-0

"Whilst we want to bring in the best players in the world, we also want to see the academy continue to develop talent and give (manager) Mark Hughes the chance to bring home-grown players into the team.

"We will back his judgement in what players to bring in and we look forward to working more closely with him in the future. We are building a structure for the future not just a team of all-stars."

RICHEST CLUB

The Middle Eastern billionaire's takeover from Thaksin Shinawatra theoretically makes City the league's richest club -- taking the mantle held by Chelsea for the last five years under Russian owner Roman Abramovich.

The new owners signalled their intentions on the final day of the transfer window by buying Brazil [Images] forward Robinho from Real Madrid [Images] for a British record 32.5 million pounds ($59.95 million).

"I am a football fan, and I hope that you will soon see that I am now also a Manchester City fan," Sheikh Mansour said.

"But I am also a long-term investor and that is probably more important to the club and to you because it means we are here for the long haul and that we will act always in the best interests of the club and all of its stakeholders, but especially you the fans."

Chairman designate Khaldoon Al Mubarak published a letter on the website earlier in the day promising that the new owners planned to build a dynasty over the next 10 years, with Hughes the key to sustained success.

"Nothing rash is going to happen, we are not going to do crazy stuff," he said.

"We will work with (executive chairman) Garry Cook and Mark. They call the shots and we are here to support to help build a sustainable club."

In the wake of the resignations of Newcastle United boss Kevin Keegan and West Ham United's Alan Curbishley over boardroom interference, Al Mubarak reassured the club's fans that Hughes would make the decisions about players.

"We are here to learn," he said. "One thing I have made very clear to Mark is that any player he wants comes from him. It comes from his requirements, his plan for the club. I'm a fan, but I am not an expert.

"It is Mark who runs the club and Mark who makes the football decisions. We are here as long-term investors, and it makes sense for us to build a dynasty. Between Mark and Garry, I think we have a dynasty in the making."

City have started the new season well and are fifth in the standings after thrashing Portsmouth 6-0 on Sunday.

• Complete football coverage