Prime Minister Scott Morrison has returned two negative COVID tests after he was deemed to be a casual contact of a positive case by NSW Health.

Mr Morrison was notified late on Tuesday that an event he was at on the previous Friday was an exposure location but has since been told he does not need to isolate.

Friday’s event is being widely reported as the graduation gala for Kincoppal-Rose Bay, School of the Sacred Heart, at the International Convention Centre Darling Harbour.

It is understood that NSW Health and the chief medical officer provided advice to Mr Morrison that an event at Kirribilli House with the South Korean president could go ahead on Tuesday night.

Mr Morrison had another test on day six of his exposure, in line with NSW Health guidelines with his planned trip to Queensland on Wednesday. He told Brisbane radio he had been given the all-clear to travel.

“The virus is there, Omicron is in Australia and we’re going to live with this virus. We’re not letting it drag us back where we’ve been,” he said on Wednesday.

“We’ve got to keep moving forward. We can’t slip back.”

The news comes as Australia opens to visa holders almost two years after the nation’s international borders closed due to the pandemic.

From Wednesday skilled workers and international students are allowed to come into Australia without needing a travel exemption.

It follows the federal government’s two-week pause on visa holders being able to return over concern about the arrival of the Omicron variant of COVID-19.

Despite Omicron leading to spikes in case numbers in several states, the pause will end on schedule.

The resumption means a travel bubble with Japan and South Korea can also begin.

The government estimates about 235,000 visa holders would be eligible to enter the country, including an estimated 133,000 international students.

Universities Australia chief executive Catriona Jackson said she was delighted international students could at last return.

“We have missed their presence dearly and couldn’t be more delighted to welcome them back from today,” Ms Jackson said.

“We recognise the very real effects COVID-19 has had on their wellbeing, and the resilience they have shown amidst extreme uncertainty.”

Wednesday also marks the reopening of Tasmania’s border, with fully vaccinated travellers able to enter the state.

People entering Tasmania from certain high-risk areas must return a negative COVID-19 test in the 72 hours before they arrive. Unvaccinated people will still need to apply for a travel exemption to enter.

Virus restrictions are also set to relax from Wednesday in NSW, with the unvaccinated able to enter retail and hospitality venues.

The ban on unvaccinated people was set to end on December 15 or when NSW hit a 95 per cent fully vaccinated rate, whichever came first.

NSW’s vaccination rate sits at 93.2 per cent.

There have been fears the decision to open up to the unvaccinated will lead to an even bigger spike in virus cases in the state, after NSW posted a large rise in infections due to Omicron.

There were 804 cases in NSW on Tuesday, the highest number since the end of the COVID-19 lockdown. They included 21 linked to the Omicron variant.

NSW announced on Tuesday night that fully vaccinated arrivals from eight southern African countries would no longer have to enter 14 days of hotel quarantine, bringing all international arrivals under the same requirements.

NSW chief health officer Kerry Chant said all fully vaccinated international arrivals must still self-isolate for 72 hours.

-with AAP