Brazilian authorities said Monday they were slapping a $17.5 million fine on US oil firm Chevron in connection with a major spill off Rio de Janeiro state last year.

Magda Chambriard, director general of the National Petroleum Agency (ANP), told a press conference that the new fine covered 24 infractions.

"There is one (missing fine) related to the abandonment of the well. The maximum limit is one million reais under the law," Chambriard said, adding that it would be imposed "in the next two months".

And Chevron could be hit with an additional fine of $50,000 for "other items".

Brazil's national oil regulator estimated that 2,400 barrels of crude were spilled in the November accident.

A report by ANP released in July accused Chevron of negligence and said the company could have avoided the spill which occurred in the Frade field, located 370 kilometers (230 miles) northwest of Rio.

In August, a Brazilian court ordered Chevron and its driller Transocean to stop their oil drilling and shipping activities within 30 days.

Chambriard said ANP would appeal the court decision on the suspension of Chevron's operations "so as not to hurt oil production in Brazil," the state Agencia Brasil reported.

Brazil's state-owned oil giant Petrobras needs Chevron's assistance for its own operations.