“At the same time, we are addressing the financial challenges posed by ambitious, complex programmes, after securing a £1.8bn financial boost for defence and reducing forecast costs by £9.5bn through efficiency savings.“We are grateful for the PAC’s report on the Equipment Plan, and we will carefully review all of its recommendations.” “The F-35 programme remains on track and within budget, providing a game-changing capability for our Armed Forces. We continue to drive down costs with every purchase and remain committed to purchasing 138 F-35 Lightning aircraft.” The Department estimates that, should all identified risks materialise, the budget and cost difference for the Plan would widen to £14.8 billion, although this could still be optimistic.Meg Hillier, chair of the Public Accounts Committee said: “In terms of poor financial planning, the Ministry of Defence is a repeat offender. The Department’s progress with addressing the concerns set out in our last report on the Defence Equipment Plan has been woeful.“The MoD simply cannot afford everything it says it needs and it is not acceptable for officials to continue deferring decisions that have a bearing on its current affordability gap and longer-term risks.“A department that is unwilling or unable to take the action required to help it live within its means is failing taxpayers, who rightly expect Government to deliver the best possible value for their money.“We urge the MoD to act on our recommendations now, work with the Treasury to ensure its funding and planning models are fit for purpose, and bring some much-needed clarity to its priorities and costs.” 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. A spokesperson for the MoD said: “We are confident that we will deliver the equipment plan within budget this year, as we did last year, as we strive to ensure our military have the very best ships, aircraft and vehicles. Meg Hillier says that the MoD is failing taxpayersCredit:Fiona Hanson/PA Britain may not be be able to expand its F-35 fighter jet fleet unless a black hole in the Ministry of Defence budget is plugged, MPs have warned.A scathing report by the Public Accounts Committee has exposed how the MoD is staring at a £7 billion funding gap, which could double over the next 10 years.Under scrutiny is the F-35 fighter jet program, which is supposed to deliver some 138 F-35 Lightning aircraft over the coming decades.Britain has already signed a contract for the first batch of 48, which are estimated to cost £9.1bn by 2025, including support such as training and maintenance.But the committee say that there remains uncertainty on the plans for F-35 beyond the procurement of the first 48 jets, with clarity on future support and maintenance costs dependent on the results of current trials. The report says that without a fundamentally different financial settlement, the MoD would have to ‘de-scope, defer or delete’ projects. Its preference would be to do the latter, given that delaying programmes often increased costs and complexity.Although the Department confirmed it would have to stop some projects it was unwilling to give specific examples.Currently, the MoD forecasts £193.3 billion of equipment and support costs between 1 April 2018 and 31 March 2028. This exceeds its £186.4 billion budget, which includes a £6.2 billion contingency, by £7 billion.