Garry Cook, the Manchester City managing director, has warned the Premier League the club's new owners are thinking big on the transfer front, and that could include a bid for Cristiano Ronaldo.

Following Monday's announcement at Eastlands that the ruling family of Abu Dhabi, the oil-rich Gulf state, were preparing to buy out owner Thaksin Shinawatra, City went from being a crisis club to the richest club in the world with unlimited ambitions in less than 24 hours.

"When it comes to ambition you have to think large scale," Cook said. "We are only into the memorandum of understanding with these people but they are talking big. They have been very vocal about their ambitions for the club.

"We are entering a new era. The fans are going to see the best players in the world. That is what they are looking forward to the most."

Having made a significant statement of intent by spending £32.5million on Robinho, an attempt to prise Ronaldo from Manchester United could be on the agenda.

"Never say never in this game," Cook said. "It changes on a daily basis. Just two years ago this club was looking at a very different type of player. Now, nothing is going to stop us.

"When you are moving the club forward you stop at nothing to get some of the best players. It's very competitive but you have to rely on the manager's judgement and the player's desire to play for the club."

However, Mark Hughes, the Manchester City manager, has warned expectant fans to not presume a host of world-class stars will arrive at Eastlands in January.

"There are exceptionally talented players around that we would bring to the club if they were made available," Hughes said. "The difficulty will be getting the clubs to release those players.

"We obviously are talking about players whose clubs are involved in the Champions League. They may not be very receptive to losing those players midway through a Champions League season.

"Maybe it will be more difficult in January than people realise. But we will pursue targets we can realistically get."

It has been suggested City offered Real Madrid a blank cheque to sign Ruud van Nistelrooy on transfer deadline day, as well as trying to hijack Dimitar Berbatov's move to Old Trafford, although neither deal came off.

Robinho is pencilled in for his debut against Chelsea - the club he said he wanted to leave Real Madrid to join - when Shaun Wright-Phillips and Jo will make their home debuts.

That trio alone cost City nearly £60million, with the arrivals of Tal Ben Haim and Vincent Kompany lost amid the frenzy that has accompanied the buy-out. And, according to Cook, that is just the tip of the iceberg.

"With the trend that has just been developing, you have to assume that Mark will have more money to spend in January," he said.

"He wants to bring better players to the team although it should not be forgotten that we have one of the biggest academies in the League as well."