The benchmark palm oil contract for November delivery on the Bursa Malaysia Derivatives Exchange was down 1.1% at 2,169 ringgit ($520.64) per tonne, heading for a third straight session of losses.

Palm oil may test a support at 2,160 ringgit per tonne, a break below which could cause a fall to 2,113 ringgit, said Wang Tao, a Reuters market analyst for commodities and energy technicals.

"Palm futures opened lower, mirroring weakness in competing  vegetable oils," said a Kuala Lumpur-based trader, adding that the stronger local currency also weighed on prices.

The ringgit, palm's currency of trade, strengthened to its strongest level against the dollar in two weeks and was last up 0.2% at 4.1620. A stronger ringgit makes palm oil more expensive for holders of foreign currencies.

In other related edible oils, U.S. soy oil futures on the Chicago Board of Trade fell 0.1%, while the September soy oil contract on the Dalian exchange eased 0.1%.

U.S. grain prices lost ground, giving up some of the previous session's gains as a crop-friendly weather over the weekend in parts of the U.S. Midwest boosted hopes of bumper production.

Meanwhile, the Dalian September palm oil contract slipped 0.1%.

Palm oil prices are affected by movements in related oils that compete in the global vegetable oils market.