US energy giant Chevron and Swiss-based rig operator Transocean signed a deal with Brazilian prosecutors on Friday to settle lawsuits over an oil spill off the coast of Rio de Janeiro.

Chevron has agreed to pay $41.6 million in compensation over the leak of 3,000 barrels of crude in November 2011 from the deepwater Frade field, 370 kilometers (230 miles) northwest of the picturesque coastal city, the Rio prosecutor's office said.

The deal requires Chevron to accept "unprecedented obligations" to prevent new incidents and provide compensation to "put an end" to two civil lawsuits, the office said in a statement.

Chevron and Transocean did not immediately comment on the agreement.

The deal was reached with the consent of Brazil's National Oil Agency and the Brazilian Environmental Institute, but must be approved by a federal court.

The offshore field, which produces 60,000 barrels of oil a day, was operated by California-based Chevron and Transocean, which ran the offshore rigs.

Though relatively small, the operation was important for Brazil to reach its goal of producing two million barrels per day.

In March 2012, a second but much smaller leak was detected in the same area in the Campos basin, and Chevron voluntarily suspended its operations in Brazil.

More than a year later, in April, Chevron was authorized to partially resume oil production in Brazil.

Chevron has already paid a 35 million real (about $15 million) fine for 24 violations stemming from the first leak. The fine imposed by the nation's oil agency was reduced by 30 percent because Chevron did not appeal it.

The Brazilian Environmental Institute imposed two separate fines in 2011 totalling some $14.6 million for environmental damage and failures in the company's accident emergency plan.

A criminal suit against the companies for environmental crimes and damage to the national patrimony was dismissed in February.

Brazil owns massive oil and gas reserves under a thick layer of salt in the Atlantic Ocean.

But the country needs millions of dollars in investments to explore the reserves, which could turn Latin America's top economy into one of the biggest hydrocarbon producers in the world.

The first auction to explore the site's Libra Field will take place on October 21. Libra is the largest oil reserve discovered in Brazil's history and is believed to hold between eight billion and 12 billion barrels.