Nigeria's lower house of parliament will investigate a railway concession the government wants to grant to U.S. firm General Electric over possible procedural violations by Nigerian officials, lawmakers said on Tuesday.
The government and the GE have confirmed talks on a railway concession deal worth around $2 billion but no details have yet emerged.
Nigeria has been looking for partners to overhaul its ageing railway system, which was mainly built by British colonial rulers before the country's independence in 1960.
Yerima Ahmed, chairman of the Committee on Privatisation, which will probe the potential deal, said the government was not following proper procedures.
"The National Council on Privatisations has not been inaugurated," he said, referring to a body he said should have been consulted under the law for such a sale.
The House of Representatives approved a motion by lawmaker Chukwuemeka Ujam to "investigate the engagement of General Electric of the United States of America in violation of the Public Enterprises Act", lawmakers said.
The lawmakers did not make any allegations of wrongdoing against GE.
The government said earlier this month more talks were needed with GE on the possible concession.
The government, suffering from a slump in crude exports, wants to boost exports of food and other non-oil products but the country lacks roads or functioning railways.
But there is resistance in parliament against government plans to attract investors for Nigeria's outdated refineries, railway system or other public assets to drum up badly needed hard currency and foreign expertise.
"They have illegally launched an attempt to take over our refineries, that was resisted," said Sani Zorro, a lawmaker form the ruling All Progressives Congress, to which President Muhammadu Buhari belongs.
"They are now making attempts to take over our remaining public assets. We call them parasites," he said.
The West African country has already signed two deals worth around $5 billion with China Civil Engineering Construction Corp (CCECC), part of China's state-owned railway construction firm, to modernise and build railways in the north and south of the country, the Nigerian Transport Ministry has said.