A suezmax tanker off the coast of Peru was involved in an oil spill after it was rocked by waves caused by Saturday's volcanic eruption in Tonga, more than 10,000 km away.

The ship was reportedly unloading when "the violence of the waves" caused a "limited spill", according to a statement from La Pampilla refinery cited by Reuters on Monday.

Media reports and Peruvian authorities said the 158,300-dwt Mare Doricum (built 2009) was involved in the spill.