This will almost double the size of the Moscow metro to 553km.

"We decided to allocate Roubles 160-170bn ($US 5.5-5.9bn) to construct the additional lines which will be able to transport millions of people," says Sobyanin. "The project will definitely help to relieve the transport situation in Moscow. The metro today is overloaded by 40% - a similar situation seen only in Tokyo.

"This is a very serious project, and we are implementing it together with the Ministry of Transport and Russian Railways. Moscow city will invest the necessary amount of funds and Moscow region will also offer support."

Sobyanin says he expects to start to see the benefit of the investment in the lines between 2017 and 2018. The new lines are expected to transport 1 billion passengers a year.