The U.S. oil giant Chevron will undergo an international-standard independent audit in the wake of a recent oil spill off the coast of Rio de Janeiro state, a Brazilian environmental official said Friday.

Chevron will foot the bill for the audit, which is estimated at 5 million U.S. dollars, said Carlos Minc, Rio state's environment secretary, adding that other oil companies operating in Rio de Janeiro will also undergo an audit, but Chevron will be the first.

The audit will analyze Chevron's capacity to respond to accidents, such as the one that happened earlier this month.

The oil leak started on Nov. 7 at a well operated by Chevron off the northeastern coast of Rio state. So far the leak is under control and the oil slick has been reduced considerably.

Chevron has already received a fine of 50 million reais (US$26.45 million) from Brazil's environmental protection agency, and may be fined by the Rio government and the Brazilian National Petroleum Agency (ANP) as well. Additional fines may be issued if investigators find out that Chevron's response to the leak was inadequate.

The ANP announced on Wednesday that all drilling activities of Chevron in its territory would be suspended until an investigation into the offshore oil spill is completed.