Business Secretary Greg Clark has waved through the sale of one Britain's oldest engineering firms to a controversial investment group.

Mr Clark dismissed claims of a "predatory" takeover as he confirmed the sale of GKN to Birmingham-based turnaround investor Melrose in the House of Commons.

The embattled engineering business, which is headquartered in Redditch, dates back to the 1900s and was instrumental in wartime manufacturing.

Labour had called for the sale of GKN to be blocked on national security grounds because the company provides many Ministry of Defence contracts but this was rejected.

Mr Clark told MPs of the numerous assurances given by Melrose as part of the £8.1 billion takeover deal.

Melrose launched its buyout bid in January but found GKN an unwilling target to begin with before shareholders eventually agreed to the hostile deal at the end of March.

Mr Clark said: "The MoD has completed its detailed analysis and has agreed with Melrose a series of undertakings specifically to ensure the Government is informed in advance of any plans to divest a business, a component of the business or assets which engage in activities the Ministry of Defence considers to have national security implications."

Mr Clark said the Government had been given "suitable protections" from any subsequent sale of the business and had been given assurances over the continuation of contractual obligations "to protect intellectual property and classified information".

Shadow business secretary Rebecca Long-Bailey told ministers the assurances were "not sufficient to guarantee security of the long-term prospects" of the company or the workforce.

She said: "Melrose are reportedly short-termist in their outlook which undermines the long-term thinking required in defence projects.

"What we needed from the secretary was not just a waving through of the deal, we needed action both in terms of obtaining concrete assurances from Melrose on the future of GKN and its workforce, but also clear plans to reform and widen our takeover regime to protect British businesses.

"I fear the short-term predators already smell their next victim and it's not just Melrose, it's Britain's industrial future."

Mr Clark hit back, telling Ms Long-Bailey she had "prejudiced her position" by advancing the takeover should be blocked from the outset and had "given away the ability to have influence".

The Business Secretary added: "This is the responsible way to proceed and she would do the employees and stakeholders of GKN a service if she would engage more forensically in future."