Some of Glasgow’s new Subway trains are undergoing testing in the city ahead of their planned introduction to the circular network next year.

Seven of the 17 trains are now in the city and are undergoing various stages of the strict testing regime required before they can carry passengers.

Transport minister Jenny Gilruth, who went to the Subway’s Govan depot to see some of the four-car trains close up, said she is “confident people will be delighted with the next generation of trains”.

She added: “The introduction of the new trains into the system will be a significant step in the modernisation programme and I look forward to visiting again when they come into service next year.”

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The trains are undergoing their initial testing at a dedicated test track built by the Stadler Hitachi joint venture, which has been contracted to deliver the trains, signalling and communication system for the Subway.

The first three trains are undergoing testing in the system at night, and recently completed their first full speed, full-circle test.

HeraldScotland: One of the brand new Glasgow subway trainsOne of the brand new Glasgow subway trains

Antony Smith, Strathclyde Partnership for Transport director of Subway, said he is pleased with how testing is going but warned “delivering the scale of this project while remaining operational is a massive challenge”.

He added: “We are at a vitally important stage now with both train-testing and signalling.

“We’ve recently had the first of a number of Sunday shutdowns to enable new signalling and communications equipment to begin to be installed in the tunnels for the new trains.”

He added the joint venture is “confident that it remains on course to see the new trains introduced into the Subway system next year”.

The new trains are part of a £288 million modernisation of the Subway, which also includes refurbishment of its 15 stations and smart ticketing.