CANBERRA, June 28 (Xinhua) -- Australian states and territories will have faster access to military personnel and resources to deal with domestic terror threats, under legislation to be introduced to federal parliament on Thursday.

Amendments to the Defence Act will enable the rapid deployment of special forces troops, military hardware and defence experts.

Previously, Australian Defence Force (ADF) assets were available only when authorities were overwhelmed.

Attorney-General Christian Porter said the new laws introduced a much more flexible threshold for states and territories to seek ADF support.

"It is designed to try and assess, at a reasonably early opportunity, whether or not there are any specific skills or assets that the ADF could bring to bear to a situation to help to protect Australian citizens from what is unfortunately an ever-present threat of domestic terrorism," Porter said.

The call-out powers are designed to deal with three key scenarios: drawn-out sieges; terror events such as those in Paris and London involving "geographically widespread, co-ordinated attacks"; and threats involving biological, chemical or radiological weapons.

The ADF comprises the Royal Australian Navy, Australian Army, Royal Australian Air Force and several tri-service units, and has 80,000 full-time personnel and active reservists.

Under the new law, it will have expanded powers to search, seize and control movement at the scene of a terrorist incident and be pre-authorized to respond to threats on land, at sea and in the air, for major events such as regional conferences.

The changes were prompted by the 16-hour Lindt cafe siege in Sydney's central business district in 2014 by lone gunman Man Monis, which ended in the deaths of two hostages. They enacted the recommendations of last year's defence counter-terrorism review ordered by Prime Minister Malcolm Turnbull.

"What the Lindt cafe siege demonstrated is that there was a very high and very inflexible threshold pursuant to which you could have the ADF participate in a response designed to help protect Australian citizens," Porter said.

Currently, states and territories must show they are not able or unlikely to be able to protect themselves or commonwealth interests.

Under the new standard, the ADF would bolster the response of state or territory authorities once the prime minister or two authorized ministers are convinced that serious violence is occurring or likely to occur.