The armed forces have been forced to cut back on car hire and the use of mobile phones in order to help raise an additional £300m to finance the renewal of the nuclear deterrent, it emerged last night.Lt Gen Mark Poffley said the Ministry of Defence has been forced to cut back across the board in order to meet its spending obligations, as he warned that “small incremental hits” to serving personnel’s quality of life could have a negative impact on retention rates.Giving evidence before the Commons defence committee, Lt Gen Poffley said in its quest to make efficiencies, the MoD had to be “vigilant” that restricting soldiers access to items such as mobile phones did not damage morale.Asked if it was “fair” that the quality of serving personnel lives should be reduced, he added: “The reality of life is fairness is not the issue. It’s about where is the best spread of our resources to deliver an output.“We are conscious that if you damage morale how that potentially manifests itself in the role of retention rates.”His warning follows reports in October that the Army had been forced to make £100m in efficiency savings to meet the costs of the Trident programme, with cuts falling on training, accommodation and travel. Answering questions from the Commons defence committee yesterday, Mr Williamson said: “I have very serious concerns about the proposed takeover.“It’s not that I’m against changes in terms of the industry, but what I want and the department wants is reassurance about the military side of the business.“This is why I have taken the decision to get in touch with Greg Clarke because we have a whole series of questions about the potential takeover and the future ownership.” It came as Gavin Williamson, the Defence Secretary, suggested to MPs that the Government could intervene in a hostile takeover of a major British defence company, amid fears that it poses a risk to national security.Mr Williamson said he had “very serious concerns” over the planned acquisition of aerospace giant GKN by Melrose Industries, an investment company accused by critics of being an “opportunistic asset stripper”.Addressing the £7bn bid yesterday, Mr Williamson said that he had written to the Business Secretary Greg Clark to seek urgent reassurances about the future of GKN’s military business.It comes several weeks after details of the bid surfaced, with MPs expressing concern that the takeover could result in GKN, which makes parts of the F-35 Anglo-American fighter jet, the Eurofighter Typhoon and the US’s B-21 stealth bomber, being broken up and sold off to firms across the world.A spokesman for Melrose said: “As a British public company we are fully aware of our ownership responsibilities with regard to all commercial stakeholders whether they be corporate customers or government.”We are happy to make this clear in any forum.” Defence Secretary Gavin WilliamsonCredit:David Mirzoeff/PA GKN, which one of the Ministry of Defence’s closest partners, employs 6,000 people in the UK and is a key supplier to aerospace firms including Airbus. The cuts are being imposed in order to control the long-term costs associated with the £31bn upgrade of four nuclear-armed submarines, with the Treasury so far failing to cede to the MoD’s demands for money. Want the best of The Telegraph direct to your email and WhatsApp? Sign up to our free twice-daily Front Page newsletter and new audio briefings.