Vale's board has approved the expansion of the Moatize coal project in Mozambique, with an investment of $6bn.
The expansion is expected to increase the output of the mine from 11Mtpa to 22Mtpa, reports Reuters.
The expansion will include construction of a new $4.4bn coal terminal at the northern port of Nacala and a 912 km rail line connecting the coal mine with the port, which will partially pass through Malawi.
The port and the line will have an initial capacity of 18Mt to meet firm's increasing demand for exports.
About 70% of the coal coming from the expansion will be coking coal, and the remaining will be thermal coal.
First production from the expanded mine is expected to start in the second half of 2014.