15/05/2015 (Reuters) - Malaysia, the world's second-largest palm grower after Indonesia, will keep its crude palm oil export tax for the month of June at zero percent, continuing duty-free exports from this month, a government circular showed on Thursday.

In April, a 4.5 percent tax was implemented, based on a tax structure where a monthly crude palm oil reference price above 2,250 ringgit per tonne leads to a duty being imposed. It can run from 4.5 percent to a maximum 8.5 percent.

In May the reference price fell below the threshold.

For June, the Southeast Asian country calculated a reference price of 2,136.05 ringgit ($598) per tonne, again below the level required for the duty to be imposed.

($1 = 3.5750 ringgit)