A prototype armoured light army tank that would give added protection and firepower for troops in Afghanistan will be displayed this week — but will not be ready for action until 2015.

The reconnaissance vehicle has been designed with a gun said to be capable of blowing holes in the thick mud walls of the compounds where Taleban insurgents take refuge — something that is beyond the armoured vehicles operating at present in Helmand province.

However, according to a prediction by General Sir David Richards, the Chief of the General Staff, the British involvement in the combat phase of the war in Afghanistan might be over by 2015. He has spoken of a British combat presence in Helmand running for the next three to five years.

The Army has been waiting since 2004 for approval for a new generation of armoured vehicles, known as Fres (future rapid effects system). But only the first stage of the programme — the Scout version — has been approved by the Ministry of Defence.

On Thursday, BAE Systems and General Dynamics will bid for the £2 billion contract with the MoD, which is expected to make a decision early next year. The rest of the Fres project, which is supposed to involve the purchase of 3,000 vehicles for about £16 billion, has been suspended.The Government has been forced by the delays to buy armoured vehicles off the shelf for Afghanistan.

The MoD has spent hundreds of millions of pounds on a wide range of different systems, each of which require separate training and spare parts and do not meet the Army’s long-term requirement for a new family of medium-weight battlefield vehicles.

“The Army's lack of suitable medium-weight armoured vehicles has meant that the MoD has had to devote considerable sums on the ad hoc purchase of systems such as Mastiff and Vector,” defence sources said.

Underlining the frustrations of the commanders in Helmand, defence industry sources said that the only way the British Task Force in the province could guarantee blowing a hole in a Taleban compound was to call for an air strike; shell it with long-range artillery; or fire a shoulder-launched Javelin missile — at £60,000 a time.

The gun for the Scout Fres is a 40mm cannon which will have superior “punch” to the 30mm Rarden gun used in the Scimitar vehicle. General Dynamic’s offer is based on a vehicle called Ascod 2.

“The 40mm high explosive round has more than three times the explosive power of the 30mm Rarden, while its armour-piercing projectile will penetrate more than 140mm of steel armour,” a BAE Systems official said.

In May 2004, Lord Bach, then the Defence Procurement Minister, predicted that the utility version of Fres - a troop-carrier - would be in service by 2009. But the in-service date has been slipping every since, and nearly a year ago, John Hutton, then Defence Secretary, said he was sending the Fres programme back to the drawing board, with the exception of the Scout variant which would go ahead as planned.

There is no longer any clear indication when the full Fres programme will be completed or whether it will ever be given ministerial approval because of expected increasing pressures on the defence budget.

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