MADRID - Real Madrid confirmed on Sunday that they have reached an agreement with striker Cristiano Ronaldo to extend his contract.

Ronaldo's previous deal had been due to expire in 2015, meaning that had Madrid not moved to renew their agreement they could have been forced to sell him at a reduced price next summer or run the risk of seeing him leave on a free transfer at the end of the following season.

The Portuguese international joined Madrid on what had been a world record deal worth 96 million euros in the summer of 2009 from Manchester United and has scored 148 goals in 139 games since then. The last of those goals came in Madrid's 2-2 draw away to Villarreal on Saturday night.

Although Real Madrid have yet to release details of the contract, it is thought he will remain at Real Madrid until 2018 and will become the highest paid player in the world with net earnings of around 18 million euros a year, which after tax will cost his club around twice that amount.