Mehr, citing unnamed provincial sources, said the action on the Nargesi oil field was taken after a complaint by Borazjan municipality in the province of Bushehr. The field is about 30 km (18.6 miles) north of the town of Borazjan.
It did not give details on when production was stopped or how long it may continue.
"Production of oil and gas at Nargesi oil field was stopped by a court order due to non-observance of environmental safeguards. The complaint by the region's municipality led to 15,000 bpd drop in Iran's oil production," Mehr said.
Iran is the world's fifth-largest oil exporter, shipping around 2.1 million bpd or about 4.5 percent of global supply.
The country pumps a total of around 3.8 million bpd, refining what it does not export for domestic consumption.
(Reporting by Hashem Kalantari; writing by Fredrik Dahl; editing by Sue Thomas)