China Railway Construction Corp. has, through its subsidiary China Civil Engineering Group Co. Ltd., signed an agreement with Nigeria’s transport ministry to build a 1,385-kilometer-long, single-track high-speed railway line with an estimated $13.1 billion price tag.

The project is expected to connect 10 Nigerian states with the capital of Lagos, but its exact route has not been disclosed because of concerns of sabotage by rebels, particularly in the oil-rich Niger delta.

Also unclear is when construction will start and the mix of workers that will build the line.

With at least 22 stations along the line, the railway has been designed to allow passenger trains to cruise at 120 km per hour.

Chinese Prime Minister Li Keqiang said during his tour of Africa in early May that the line also will open up the delta, which has been the scene of violence by gangs claiming to be ignored by the government and oil multinationals operating in the area.

China Railway Construction reported $1 billion in revenue in the first quarter of 2014, 21.15% higher than in the same period the previous year.

“Nigeria emphasizes development of railway lines and other infrastructure, while China possesses technical strength and rich experience in this regard,” said Li.

Nigerian President Goodluck Jonathan backed the rail deal with China, saying his government aims to develop a mass-transit system that can move people and freight more efficiently.

Both the Nigerian Railway Corp., which manages the country’s public rail transport, and China Railway Construction did not respond to requests for additional information.

This is the second major railway project in Nigeria to be funded and developed by China.

Last year, China Export and Import Bank provided $500 million to build a light-rail project in the Nigerian capital of Abuja, which has been contracted to China Civil Engineering Construction Corp.

The project, which will connect the airport and satellite towns to the city's downtown, is set for completion in 2015.

China Civil opened a railway-technology training center in Nigeria in 2012; the company said it was an effort to link with local technicians and artisans to improve work standards, create a worker pipeline and address the country's structural unemployment.