JAKARTA, March 27 (Reuters) - Indonesia has increased its crude palm oil reference price to $961.54 per metric ton for April, a trade ministry regulation showed on Thursday. The new price will leave the export tax for April unchanged at $124 a ton. Indonesia also currently imposes a 7.5% levy for CPO exports and a levy for more refined palm oil products of between 3% and 6% of the reference price. (Reporting by Stanley Widianto and Bernadette Christina; Editing by Martin Petty) ((mailto:Widianto.Stanley@thomsonreuters.com;))