MOSCOW - Saudi Arabia's state oil producer Aramco and Algeria's Sonatrach dropped April official selling prices (OSPs) for liquefied petroleum gas (LPG) by 0.9%-3.1% versus March due to weaker demand, traders said.

Aramco's April OSP for propane decreased by $15 to $615 per metric ton , while that for butane dropped by $20 to $620 per ton .

Propane and butane are types of LPG with different boiling points.

LPG is mainly used as fuel for cars, heating and as a feedstock for other petrochemicals.

Sonatrach cut its April OSP for propane by $5 per ton to $535 per ton and for butane by $10 per ton to $570 per ton. .

Aramco's OSPs are used as a reference for contracts to supply LPG from the Middle East to the Asia-Pacific region.

Sonatrach's OSPs are used as benchmarks for the Mediterranean, Black Sea region and Turkey.

(Reporting by Reuters;Editing by Kirsten Donovan)