Iran said it could move to sue BP over an oil spill last year  at the Azeri-Chirag-Gunashli oil platform it operates after oil from the spill washed up on Iranian beaches, Reuters reported on Wednesday.
Mehr news reported on Tuesday that BP had been dumping byproducts in the sea, which is home to some of the world’s rarest species of animals and plants.
A spokesman for BP said there had not been any need to report leaks at its sites there for years.
"We are a responsible operator in the Caspian and as such we have rigorous HSE (Health, Safety, Environment) processes and procedures in place in line with international standards," BP told Reuters in an emailed statement on Tuesday.
Iran, one of the world's largest oil producers, has seen its income dwindle as a result of sanctions on the Islamic Republic .