The deal will unlock investment worth $US 410m, which will enable GyM-Ferrovias to increase capacity on Line 1 from 320,000 to 500,000 passengers per day.

Alstom will supply 20 six-car Metropolis 9000 trains and the existing fleet of 19 Metropolis trains will be lengthened from five to six cars. The first four trains will be delivered in early 2018, enabling peak headways to be reduced from six to five minutes. The final trains will be delivered by the end of 2018, allowing services to operate at three-minute frequencies. The 10-minute interval service at weekends will be stepped up to provide a six-minute frequency.

In preparation for higher-frequency operations, the electrification system will be upgraded and alterations will be made to improve passenger flow at the line’s busiest stations: La Cultura, Grau, Gamarra, Bayóvar and Villa El Salvador.

The depot at Bayóvar will be expanded to accommodate the enlarged train fleet and stabling sidings at Villa El Salvador will be upgraded to streamline operations.

To improve flexibility and aid recovery in degraded operating conditions, bidirectional crossovers will also be installed at eight locations.