Oil companies operating in Ecuador will no longer hold a stake in the oil they produce, but will instead receive a set production fee under new rules put in place by the government.

Natural Resources Minister Wilson Pastor said the entire oil production will be owned by the state and the companies will be paid a rate for the oil produced.

The government said companies have 120 days to accept the new contract or see their oilfields confiscated by state energy company Petroecuador. Those affected include Spain’s Repsol-YPF, Brazil’s Petrobras, Chinese consortium Andes Petroleum and Agip Oil, a subsidiary of Italy’s ENI.

Opponents of the law say it will scare away investment from Ecuador’s energy industry, the country’s main money-earner, reports businessweek.com.

Ecuador, a member of OPEC, produces about 472,000 barrels per day.