SINGAPORE, June 14 (Reuters) - Malaysian palm oil futures ended at a more than four-month low on Monday, extending losses for a sixth straight session, hurt by a fall in Indonesian exports and weaker soyoil prices.

The benchmark palm oil contract for August delivery on the Bursa Malaysia Derivatives Exchange fell 285 ringgit, or 7.8%, to 3,378 ringgit ($821.30) a tonne, its lowest since Feb. 5.

Last week, palm posted its first weekly drop in three weeks, falling 11.3% on worries over tepid June exports and forecasts of higher stocks and output.

"Bursa Malaysia Derivatives Exchange crude palm oil futures are trading sharply lower following bearish momentum in CBOT (Chicago Board of Trade) soy oil futures," said Anilkumar Bagani, research head of Mumbai-based vegetable oils broker Sunvin Group, adding that lower demand also hit prices.

CBOT soyoil prices fell 3.4% to their lowest in nearly four months. U.S. President Joe Biden's administration, under pressure from labour unions and senators, is considering ways to provide relief to domestic oil refiners from biofuel blending mandates, three sources told Reuters on Friday.

Palm oil is affected by price movements in related oils as they compete for a share in the global vegetable oils market.

Meanwhile, Indonesia reported a more than 18% drop in exports for April from the prior month, raising questions about global demand for the edible oil.

($1 = 4.1130 ringgit)

(Reporting by Fathin Ungku; Editing by Subhranshu Sahu and Ramakrishnan M.)