Western Australia, South Australia and Tasmania have all imposed restrictions on travellers from Queensland as the state battles a 'significant' Covid-19 outbreak.
Tasmania was the first to impose hard border restrictions on arrivals from five government areas on Monday morning just days before the Easter break.
Effective immediately, residents arriving into Tasmania from Brisbane, Logan, Moreton Bay, Ipswich and Redlands will have to enter quarantine for two weeks.
South Australia has also declared Brisbane to be a hotspot and will require arrivals to undergo 14 days of self-isolation from 4pm on Monday.
A health care worker is seen collecting information from motorists waiting in line to be COVID tested in Brisbane on Monday
On Saturday, WA Premier Mark McGowan announced all arrivals from Queensland would have to self-isolate for 14 days as part of a 'soft' border closure.
From 5pm on Monday, Brisbane will enter into a three-day lockdown after the four new local coronavirus cases were found amid an outbreak of the highly-contagious UK variant in Queensland.
Monday's announcement brings the total number of cases in Brisbane cluster to seven, with six other infections found in hotel quarantine.
Three of the four new cases are close contacts of known cases, but those infected may have been out in the community - raising the risk more transmission may have occurred.
Brisbane will enter a three-day lockdown from 5pm on Monday after four new cases of Covid-19
Two of the cases - a nurse and her sister - visited the popular tourist town of Byron Bay in northern NSW while infectious, sparking fears the virus has already spread interstate.
The snap lockdown in Greater Brisbane, including Brisbane, Logan, Moreton Bay, Ipswich and Redlands, means pubs, restaurants and cafes will shut except for takeaway, with millions only allowed to leave home for essential reasons.
More to come