These are the new-look trains headed for Perth's rail network — and for the first time in almost 30 years, the city's rail cars will be built locally.

Key points: A total of 246 new rail cars will be built, each with capacity for 1,200 passengers

A total of 246 new rail cars will be built, each with capacity for 1,200 passengers The deal requires manufacturer Alstom to build half of the rail cars locally

The deal requires manufacturer Alstom to build half of the rail cars locally The Government says the price per rail car is cheaper than before, at $2.97 million

The McGowan Government has formally signed a 10-year, $1.3 billion contract with global train manufacturer Alstom to build 246 new rail cars to service the Metronet project.

The deal fulfils an election commitment to return local rail car manufacturing to WA, following the closure of the Midland Railway Workshops in 1994.

The new rail cars will each have capacity for 1,200 passengers, with USB ports to charge electronic devices, extra doors to improve passenger flow and improved seating options and information displays.

Manufacturer Alstom says the interior of the trains will be made and purchased locally. ( Supplied: WA Government )

Alstom said improved traction technology would ensure smoother acceleration and braking throughout the rail journey.

The contract also includes six diesel rail cars to replace existing rolling stock on the Australind rail service, along with a new manufacturing and assembly plant in Bellevue, a short distance from the original railway workshops.

The plant will also be used to carry out rail car maintenance for the next 30 years.

"The project is not only one of the largest contracts in Western Australia, it's also the largest single contract that Alstom has ever secured in Australia," Alstom Australia and New Zealand managing director Mark Coxon said.

Half of rail cars to be made in WA

The contract is expected to create 200 direct local jobs and requires Alstom to build 50 per cent of the rail cars locally.

"On rail cars manufactured before this announcement, there was about 2 per cent local content. We are increasing that 25-fold," WA Premier Mark McGowan said.

A total of 246 new rail cars will be built to service the Metronet project. ( Supplied: WA Government )

Mr Coxon said the rail car shells would be imported from overseas, but other features would be made here.

"We will be integrating locally-made electrical cubicles, the whole interior will be purchased locally — so seats, flooring, windows — as well as the drive cabin itself will be manufactured locally," he said.

Until now, new rail cars for the WA network were predominately built in Queensland.

The State Government would not say whether it had analysed the cost of having the entire rail cars built overseas, but insisted the deal represented value for taxpayers.

Each rail car will cost $2.97 million under the new contract, the WA Government says. ( Supplied: WA Government )

"The price we're paying … per rail car is cheaper than the previous ones bought under the previous government. That is value for money," Transport Minister Rita Saffioti said.

She said that was achieved by increasing the size and length of the contract.

Ms Saffioti said the cost per rail car under the last order of B-Series trains was $4.05 million, while the cost under the new contract was $2.97 million.

Jobs welcome but concern over delays

Shadow Transport Minister Libby Mettam said she supported local jobs and manufacturing but criticised the time taken to secure the contract.

The trains will have extra doors plus better seating options and information displays. ( Supplied: WA Government )

"The fact that it's taken over two years for the contract to be signed again raises concerns about this Government's ability to deliver transport projects for this state," she said.

But the Australian Manufacturing Workers' Union (AMWU) welcomed the deal.

"This is an important milestone for local manufacturing in our state," AMWU state secretary Steve McCartney said.

"In the past, our trains were built in Queensland and overseas with only 2 per cent of the work completed here.

"This contract demonstrates real manufacturing in WA, not a construction of some flat-packed train from overseas."