MADRID (Reuters) - Spain will be guaranteed at least two MotoGP races for the next five years after promoters Dorna announced a contract extension for the MotorLand Aragon circuit on Thursday in addition to Valencia.

The 18-race world championship currently has four Spanish rounds, with Jerez and Barcelona's Circuit de Catalunya the other two.

A provisional 2017 calendar published this week also had all four Spanish races remaining.

"It's a great pleasure to sign another contract to extend MotoGP at MotorLand until 2021," said Dorna chief executive Carmelo Ezpeleta in a statement ahead of this weekend's race. Valencia's extension was announced on Tuesday.

(Reporting by Alan Baldwin, editing by Pritha Sarkar)