Rio de Janeiro: Brazil's oil industry watchdog ANP said on Friday it issued a third citation against Chevron for a November oil spill at the Frade offshore field, signalling that regulators are stepping up oversight of the No 2 US oil company's offshore operations in the South American country.

ANP can fine Chevron up to 50 million reals (Dh98.6 million) for each citation.

Chevron failed to put in practice procedures that would slow the depletion of reservoirs at the well in the Frade field, ANP said in a statement sent to reporters by email.

Also, Chevron has been cited in a $20 billion (Dh73.5 billion) civil lawsuit filed by public prosecutors regarding the oil spill. Brazilian federal police have indicted Chevron, the drilling company Transocean and executives from both companies in a criminal case alleging environmental crimes and obstruction of justice.

Agreed plan

The procedures the ANP alleges Chevron failed to meet had been agreed to in a development plan approved by the agency. Failure to follow the plan led to the leaking of oil from the reservoir, the statement said.

ANP did not say how much it planned to fine Chevron.

The US company said in a statement later on Friday that it will analyse ANP's allegations but added it was "confident that it has always acted in a diligent and appropriate way", and accordingly to the development plan approved by ANP.