The 1524mm-gauge type 81-722/723/724 sets were ordered in September 2016 in a deal worth Roubles 13.4bn ($US 223m). OEVRZ will deliver a second train this month and St Petersburg Metro will receive a total of 15 trains by the end of the year, with the balance due for delivery in 2017.

Each train is formed of two three-car sets, each comprising a driving trailer and two motorised cars. The trains are equipped with asynchronous traction motors, which are expected to reduce energy consumption by 30% compared with existing trains.

OEVRZ is also supplying 20 eight-car trains to St Petersburg under a separate contract, with deliveries due for completion in 2020.