The decision, which has bilateral political support, means women will be permitted to perform any role, provided they meet the physical and psychological requirements. The changes, to be phased in over the next five years, could lead to them serving in infantry combat units and special forces.
The Defence Minister, Stephen Smith, yesterday called the move "a significant and major cultural change". He said: "Once this is fully implemented, there will be no restrictions. If a woman is fully capable of doing the entrance programme for the Special Air Service or Commandos, [they can join]."
Canada, New Zealand, Denmark and Israel have already opened up combat roles to women who pass the entry tests. Britain and the US exclude women from dedicated infantry roles. In Australia, women have been barred from serving as front-line infantry and artillery soldiers, navy clearance divers, mine-disposal experts and airfield guards.
The lifting of the ban comes as Australia reviews the treatment of women in its military folllowing a number of sex scandals, including the broadcasting on Skype of a female cadet having sex with a fellow recruit at the Defence Force Academy in Canberra.
While the decision has the backing of defence force chiefs, the Australian Defence Association, an influential security think-tank, accused the government of "jumping the gun". It said that research was still under way into women's capabilities in the military.
The association's head, Neil James, told ABC radio: "The issue they don't appear to be willing to address is the risk of disproportionate casualties. Someone, is going to have to face the people of Australia and explain why we're killing our female diggers [soldiers] in larger numbers than our male diggers." Most jobs in the Australian military are already open to women, who can serve on submarines and as Air Force fighter pilots. In Afghanistan, they serve with front-line artillery units and as drone-aircraft operators. However, they are excluded from infantry combat units and special forces – representing about 7 per cent of army jobs.
The changes will be phased in gradually to ensure that female combatants have the necessary training and preparation. Currently, women fill about 10,000 of the 81,000 regular and reserve positions in the armed forces.
Mr Smith does not expect any opposition from foreign allies, including US troops serving with Australian soldiers in Afghanistan. He said the government and service chiefs saw the move as "a logical extension to the very strongly held view in Australian society that all of us are equal, irrespective of our backgrounds and irrespective of our sex".
The decision clears the way for women, in the future, to lead infantry companies and to command the military as chief of defence – a role until now confined to men.
Critics argue that biomechanical differences between the sexes mean that even physically strong women are more vulnerable in combat. Entry requirements for the SAS are particularly gruelling, involving endurance marches and mental tests over several days in the sweltering Outback, while carrying weapons, water and an 80kg pack.