Peruvian President Pedro Castillo decrees major oil spill an environmental emergency

Peruvian President Pedro Castillo has declared an environmental emergency after a huge oil spill at the country's biggest refinery.

Peruvian President Pedro Castillo declared an environmental emergency on Thursday as clean-up teams struggled to contain a huge oil spill at the country's biggest refinery, after rogue waves rocked a ship unloading crude there.

The spill, blamed on unusual swells caused by a volcanic eruption thousands of miles away in Tonga on Sunday, has dirtied waters and beaches along Peru's Pacific coast, with dead birds and seals washing up on shore.

"We are at a critical moment in environmental matters," said Castillo, before signing the emergency decree on one of the beaches hit by the spill. "This is the most worrying ecological disaster on the Peruvian coast in recent times."

"We cannot shy away from responsibilities, it is about assuming them, in this case the company that caused this ecological disaster," he added.

A spokeswoman for La Pampilla refinery, owned by Spanish energy firm Repsol, has said the firm was not responsible for the spill and blamed the Peruvian Navy for not issuing a tsunami warning after the Tonga eruption.

Unlike other Pacific countries, Peruvian authorities warned of unusual waves only after the eruption.

Environment Minister Ruben Ramirez has said that some 6,000 barrels of oil were spilled in the incident, which has left oil on 21 beaches.