Egypt on Tuesday signed a 15-year, billion-euro contract with French transport operator RATP Dev to manage Cairo's third metro line, the transport ministry said.

The government has sought to expand the run-down network in recent years to ease the burden on the traffic-choked streets of the capital, home to more than 20 million people.

In 2012 its third metro line went into operation, stretching 47 kilometres (29 miles) from east to west.

The new 1.1 billion-euro ($1.4-billion) contract between RATP Dev and the National Tunnels Authority aims "to alleviate the pressure on the Egyptian Company for the Management and Operation of the metro, which is in charge of the first and second lines," the transport ministry said.

Over three million commuters use the Cairo metro every day, but the metro company has been grappling with heavy losses and debts for years.

The government has hiked fares several times in recent years to generate funds for upkeep of the three-decade-old network.

In August, authorities raised the metro tickets covering up to nine stops from three to five Egyptian pounds ($0.32).

The fare for up to 16 stops now costs seven pounds ($0.44).

A third of Egyptians live below the poverty line.