Lockdowns only to be used in 'extreme circumstances' under 'post-vaccination' phase

Lockdowns and border controls could become a last resort under the government's new four-phase plan to move Australia forward in its vaccination rollout.

Tough travel restrictions and stay at home orders will only to be used 'in extreme circumstances' once Australia reaches a designated vaccination target, Prime Minister Scott Morrison said.

Australia will enter a post-vaccination phase once the country reaches a vaccination threshold to be determined by a modelling process.

LIVE UPDATES: PM unveils four-point plan out of pandemic

Mr Morrison said the threshold would be a "scientific number".

"It won't be a political number, it won't be an arbitrary number, it will be a number that we can have confidence (in)."

Once the target has been met, Australia will move into a phase where it would seek to minimise serious illness, hospitalisation and fatality as a result of COVID-19.

READ MORE: Uptick in NSW COVID cases, with 'concerning' number active in community

This would mean restrictions would ease for vaccinated residents, including lockdowns and border controls.

"Lockdowns would only occur in extreme circumstances to prevent escalating hospitalisation and fatality," Mr Morrison said.

As it currently stands, there are no specific guidelines for lockdowns or border controls.

States are responsible for managing their own COVID-19 restrictions and there are no national standards on when these restrictions should be introduced.

READ MORE: Brisbane, Moreton Bay lockdowns extended after three new local cases

Since the beginning of the pandemic, snap lockdowns and changes to travel restrictions have been an ongoing point of controversy with the public struggling to keep up with fast changes.