Britain's armed forces should adapt to new forms of warfare and tight budgets by giving priority to troops on the ground and spending less on expensive weapons systems, the head of the British army said on Monday.

Britain's military is wrestling with the quandary of how to equip its 9,500 troops in Afghanistan and pay for multi-billion-dollar defence projects at a time when public spending is set to be squeezed to rein in a ballooning deficit.

Both the Labour Party and the Conservatives are committed to a strategic defence review if they win an election due by June. A think tank predicted last week Britain's armed forces may shrink by a fifth in the next six years.

Army chief General David Richards said the British defence establishment had not fully adapted to the security realities of the post-Cold War world.

Modern conflict was mainly about winning hearts and minds on a mass scale, he said, and this required mass numbers, whether of "boots on the ground," river and high-speed coastal warships, drones, transport aircraft or helicopters, he said.

"If one equips more for this type of conflict while significantly reducing investment in higher-end war-fighting capability, suddenly one can buy an impressive amount of 'kit'," he said in a speech to the International Institute for Strategic Studies.

"While ... I am emphatically not advocating getting rid of all such equipment, one can buy a lot of UAVs (unmanned aerial vehicles or drones) or satellite technology for the cost of a few JSF (Joint Strike Fighters) and heavy tanks," he said.

PROGRAMMES UNDER SPOTLIGHT

The planned strategic defence review is likely to take a long, hard look at programmes such as the Typhoon fighter, the Joint Strike Fighter, aircraft carriers, destroyers and Trident nuclear submarines, all of which will require heavy investment in the coming decade.

It is likely to pit the British army against the Royal Air Force and the Navy as each service lobbies to preserve its funding in the current 36 billion pound defence budget.

Former military chiefs accused Prime Minister Gordon Brown last year of failing to provide British troops in Afghanistan with enough helicopters or heavily-armoured vehicles, putting lives at risk.

Richards countered the argument that a switch to more basic equipment could leave Britain exposed if it came to fighting a conventional war by suggesting that any potential enemy country would also adopt methods used by al Qaeda or the Taliban.

"Having learned the lessons taught by al Qaeda, the Taliban and many other non-state actors ... why would even a major belligerent state choose to achieve our downfall through high-risk, high-cost traditional means when they can plausibly achieve their aims ... using proxies, guerrillas, economic subterfuge and cyber warfare?," he asked.

Britain could make up for a lack of military capability in any area through alliances with other countries, he suggested.

He implicitly criticised the Labour government by saying he would favour having more regular defence reviews, perhaps every five or eight years. The government last held a review 12 years ago.