LAGOS (Reuters) – A Nigerian court on Wednesday dismissed government claims that subsidiaries of Eni and Petrobras illegally exported crude oil to the United States, but a lawyer representing authorities in the West African country said an appeal would be launched.

Crude oil sales are the mainstay of Africa’s biggest economy, making up two-thirds of the country’s revenue and around 90 percent of foreign-exchange earnings.

In a lawsuit filed in 2016, Nigeria alleged that a number of companies exported a total of 57 million barrels of crude oil to the United States between 2011 and 2014. It said they failed to declare all of this to Nigeria’s government as required by law.

A judge at the federal high court in the commercial capital Lagos said the government had failed to provide enough evidence to support its suit against the local Agip unit of Italy’s Eni and the Brasoil unit of Brazil’s state-run Petroleo Brasileiro SA, better known as Petrobras.

“The court did not agree with our position,” said Ituah Imhanze, a lawyer who represented Nigeria’s government in court.

He said the government would file an appeal by the end of Thursday.

Representatives of Eni and Petrobras did not immediately respond to an email requesting comment.