Britain's 'withered' armed forces can NOT defend us against Russia says ex-defence chief as it is revealed army last practised full armoured warfare three years before Twitter was born 

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Britain's armed forces would not be able to protect the country from a full-scale attack by Russia, the recently retired commander of Joint Forces Command has warned.

General Sir Richard Barrons, who left his post in April, delivered a scathing assessment of the UK military in a 10 page private memo to Defence Secretary Sir Michael Fallon.

He said Whitehall was focused on 'skinning' budgets and maintaining expensive but redundant high-profile military capability. 

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General Sir Richard Barrons said armed forces capability had been withered by design

There are concerns Britain 'cannot afford to use fully' Britain's new aircraft carriers (HMS Queen Elizabeth pictured) 

It comes despite the Government's decision to increase defence spending by almost £5 billion by 2020/21 and to meet Nato's target to spend two per cent of GDP on defence for the rest of the decade.

In his memo, Sir Richard, who was one of four service chiefs, said: 'Capability that is foundational to all major armed forces has been withered by design.'

He went on: 'There is a sense that modern conflict is ordained to be only as small and as short term as we want to afford - and that is absurd.

'The failure to come to terms with this will not matter at all if we are lucky in the way the world happens to turn out but it could matter a very great deal if even a few of the risks now at large conspire against the UK.'

The document, seen by the Financial Times, gives a withering judgment of the country's ability to defend itself against a full-scale military attack and singles out Russia, a country seen as more dangerous and unpredictable since its annexation of the Crimea and incursion in Ukraine.

Nato countries will be concerned as Britain is seen as the prevailing European military power within the alliance. The US has however had growing fears over its diminishing capacity since lengthy and expensive wars in Iraq and Afghanistan.  

Sir Richard said: 'Counter-terrorism is the limit of up-to-date plans and preparations to secure our airspace, waters and territory ... there is no top-to-bottom command and control mechanism, preparation or training in place for the UK armed forces (to defend home territory) ... let alone to do so with Nato.'

On Britain's ability to defend itself from aerial attack from Russia, he said: 'UK air defence now consists of the (working) Type 45 (destroyers), enough ground-based air defence to protect roughly Whitehall only, and RAF fast jets.

'Neither the UK homeland nor a deployed force - let alone both concurrently - could be protected from a concerted Russian air effort.'

Sir Richard said the Army's recent experience does not include conducting full scale wars, which could be a disadvantage. The last time the Army conducted proper armoured warfare was in 2003 - three years before the birth of Twitter.

'The current Army has grown used to operating from safe bases in the middle of its operating area, against opponents who do not manoeuvre at scale, have no protected mobility, no air defence, no substantial artillery, no electronic warfare capability, nor - especially - an air force or recourse to conventional ballistic or cruise missiles,' he said.

Sir Richard also raised concerns that Britain's armed forces are dominated by small numbers of expensive equipment such as the new £2bn each aircraft carriers which 'we cannot afford to use fully, damage or lose' and bemoaned a lack of manpower across the military. 

Military expert Ben Barry claimed the RAF would only be able to deploy six of its ordered 48 F35B Lightning fast jets

It was revealed yesterday the Navy's new Type 45 destroyers had notched up a staggering 1,515 days in UK harbours between April 2015 and April this year

He added that diminishing manpower meant Russia would not need to shoot down Britain's new Joint Strike Fighters - but 'murder' the 40 pilots who can fly them. 

Major General Tim Cross, who served in the Army for nearly 40 years, rejected suggestions Sir Richard's comments were a case of 'sour grapes' because he was overlooked for promotion.

Maj Gen Cross said such assumptions were 'unfair and wrong', and that Sir Richard was an 'extremely capable operator'.

'Like all commanders, and I did this myself when I handed over command of my division, what Richard has done is produce what we call a haul down report,' he told BBC Radio 4's Today programme.

'A haul down report is a state of the nation, it's a final shot to say to the system - in this case the Secretary of State because Richard was a four-star general - 'this is my command, this is what it looks like, these are my concerns', and he's laid those out.

'He's speaking truth into power and it's a normal thing to be doing.'

Maj Gen Cross said the UK would no longer be fighting 'conventional wars' and has been through a period of 'wars of choice' - deciding whether or not to get involved. 

He added: 'The concern today, and it's not a new concern, it's been emerging over the last few years, is the re-emergence of Russia, of China, and the need to be capable of fighting a conventional war in the old style sense, as opposed to those in Iraq, Afghanistan and counter-terrorism.

'There's no doubt that we need to look at the issues Richard has highlighted, because the problem is the equipment for this sort of campaign is hugely expensive.'

Gen Cross told the BBC that Sir Richard was responsible for the 'hugely important' Joint Force Command, which 'looks pan-defence', examining cyber warfare, logistics and surveillance among other areas. 

Ben Barry, senior fellow for land warfare at the International Institute for Strategic Studies, backed Sir Richard's assessment.

On the fast F35B Lightnings, he claimed the RAF would only be able to fly six of the 48 fast jets Britain was committed to purchasing at any one time. 

For a 'high-tempo' mission up to 12 could be deployed for a short period, he added.