CALLING a halt on the £500m race to build a new Metro fleet to help a North East-based firm would be illegal and risk heavy delays in the upgraded trains arriving, transport bosses insist.

Tyne and Wear leaders have rejected calls from Tees Valley mayor Ben Houchen to pause the procurement process for the fleet, amid claims that Hitachi is set to fail in its bid to build the new stock.

The Conservative mayor said that it would be “appalling” not to give the massive contract to the Japanese company, which has a base in Newton Aycliffe.

But Tobyn Hughes, managing director of Metro operator Nexus, warned on Thursday morning that such a move would be illegal and “unfair to taxpayers”.

Labour councillors accused the mayor of playing political games with the future of the ageing rail network.

Mr Hughes told the North East Joint Transport Committee’s Tyne and Wear sub-committee: “Some people might have a preference for who they would like to see win the contract.

“Provided that they are not involved in the procurement process they are of course entitled to have an opinion and to express it.

“Nexus, however, is absolutely not entitled to award contracts based on personal preferences or subjective judgements.

“That would be unfair to the companies who are spending time and money competing for the contract in good faith, unfair to taxpayers who could end up spending more money than is necessary, and unfair to our passengers who deserve to travel on the best possible trains long into the future.

“For good measure, Nexus is a public body, it would be against the law. To ignore that fact would risk costly legal challenges and would add yet more time to the process of getting new Metro trains onto the system, already long overdue.

“This process is fundamentally about improving life for Metro’s passengers, using public money. Outside commentators are likely to have different objectives.”

Alongside Hitachi, Spanish firm CAD and Swiss manufacturing giant Stadler also remain in the running for a £500m contract to build and maintain the fleet and a new depot.

Mr Hughes said that North East suppliers would benefit regardless of who is chosen for the “once in a lifetime” project, and reiterated that no decision will be announced until January.

North Tyneside councillor Carl Johnson said: “For the mayor to ask for the process to be paused is quite frankly ridiculous.”

He added: “Ben Houchen is playing a completely political game. He knows he has got an election next year and he needs a big political point to win, that is exactly what he is doing.”

Gateshead transport chief Coun John McElroy accused the mayor of “promoting himself to the Mayor of the North East” and said a pause in the procurement process would be “subject to legal challenge and would be very irresponsible with taxpayers’ money”.

The new trains will have air conditioning, Tube-style linear seating to increase capacity, wider doors and aisles, and digital features such as wi-fi connectivity and charging points.

Mr Houchen’s office has been contacted for a response.