Scott Morrison says he has tested positive to Covid-19 after experiencing flu-like symptoms.
The prime minister announced the test result on Twitter around 11:30pm on Tuesday, but insisted he will continue to work from home while isolating.
"I am experiencing flu-like symptoms and will be recovering over the next week," he wrote.
"I had tested myself daily since Sunday, including this morning, with all tests returning a negative result," he said.
"I took a further test this evening after developing a fever late today. The test was inconclusive so I took a PCR test tonight which returned a positive result late this evening.
"I am continuing to follow health guidelines and am isolating at home in Sydney."
Mr Morrison had been scheduled to attend an event in Sydney on Tuesday night, alongside NSW Premier Dominic Perrottet as the Opera House was lit up with the colours of the Ukrainian flag, but cancelled shortly before 8pm.
Earlier on Tuesday, Mr Morrison took part in a meeting of the federal cabinet's national security committee and held a press conference with Defence Minister Peter Dutton.
He also met Nauru President Lionel Aingimea in Sydney, according to a post on his Twitter account.
Tonight I tested positive to COVID-19.
I am experiencing flu-like symptoms and will be recovering over the next week.
I had tested myself daily since Sunday, including this morning, with all tests returning a negative result.
— Scott Morrison (@ScottMorrisonMP) March 1, 2022
Mr Morrison said his wife Jenny and two children had tested negative and will isolate for seven days at home as close contacts.
"While in isolation I will continue to discharge all my responsibilities as Prime Minister... focusing on our emergency response to the devastating floods in Queensland and New South Wales, and ensuring we stand with each and every one of the affected communities both now and as the waters eventually recede," he said.
He added he would also be "focused on our urgent response to the tragedy unfolding in the Ukraine and Russia's senseless aggression, staying in regular contact with our security and intelligence officials and our international partners, as well as working with the Treasurer to finalise the budget".
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