A cable for data transmission called EllaLink will be laid under the Atlantic from Sines harbour in Portugal to the city of Fortaleza in Brazil, Xinhua reports.
The Chinese government-run news agency quotes a written statement issued by the local government in Sines as saying the cable will also serve Cabo Verde and the Portuguese island-region of Madeira, carrying data at the rate of 73 terabits per second.
The report says EllaLink will cost 170 million euros (US$186 million), and may begin carrying data in 2020.
It quotes Mayor Nuno Mascarenhas of Sines as saying EllaLink will help make his city a hub for innovation.
EllaLink is developed under the BELLA project (Building European Link to Latin America), a joint endeavour by European and South American countries, and is being funded by the European Commission and the private sector, Xinhua says.