The first order for 33 trains was placed in 2003, and KTP exercised options for 30 trains in 2005, 20 in 2008, and 32 in 2010, taking the total to 115. The delivery of the new trains has allowed the replacement of older T1000 and T1300 stock, giving Oslo a uniform fleet of the new Siemens trains.

The aluminium-bodied MX3000s are being assembled at Siemens' Simmering plant in Vienna and the final train is due to be delivered to the Norwegian capital in the second quarter of next year. Each 54m-long set accommodates up to 678 passengers and Siemens says regenerative braking recovers up to 46% of power consumption.

The contract is Siemens' largest ever contract for metro trains.