JAKARTA (Reuters) - Indonesia's second largest party, Golkar, will support former general Prabowo Subianto in July's presidential election, a senior party official said on Monday.

The move came as a surprise as many expected Golkar to throw its support behind presidential frontrunner Joko "Jokowi" Widodo, who earlier on Monday named Golkar senior party official and former vice president, Jusuf Kalla, as his running mate.

Golkar Chairman Aburizal Bakrie also said last week he would cooperate with Jokowi's coalition ahead of the July election.

"At (Golkar's national meeting), Aburizal Bakrie gave a statement that the whole Golkar family and party will give its full support to (Prabowo as president and Hatta as vice president)," said Golkar's Secretary General Idrus Marham at a political rally.

(Reporting by Kanupriya Kapoor; Editing by Simon Cameron-Moore)