SINGAPORE: Singapore port authorities are cleaning up an oil spill caused by a collision between two bulk carriers earlier on Tuesday, the city state's Maritime Port Authority said in a statement.

Around 100 metric tonnes, or 700 barrels, of fuel oil spilled into the sea, according to the MPA.

Vessel traffic in the Strait of Singapore and port waters and port operations remained unaffected, the MPA said.

There was a collision between South Korea-registered bulk carrier Oriental Pioneer and Bahama-registered Atlantic Hero about 6.6 kilometres off Singapore's Tanah Merah Ferry Terminal, the MPA said.

The port authority is investigating the cause of the collision.