The Federal Government has extended its coronavirus travel ban for travellers from Italy, South Korea, Iran and China for another week as the number of Australian cases continues to rise.

Key points: The decision was made by Cabinet's national security committee based on advice from the nation's chief medical officers

The decision was made by Cabinet's national security committee based on advice from the nation's chief medical officers No ban is in place for the US despite a spike in virus cases

No ban is in place for the US despite a spike in virus cases Australian citizens and permanent residents can return home but must isolate themselves afterwards

The Prime Minister had asked health officials to also consider extending the restrictions to all travellers from Europe, but the Government confirmed on Thursday evening there would be no ban at this stage.

The extension was announced a day after it expanded the travel ban to include visitors from Italy, which is currently grappling with the largest outbreak of the virus outside China.

The extension means foreign nationals who have been in any of the four nations will not be allowed into Australia for 14 days from the time they left those countries.

Australian citizens and permanent residents travelling from those countries will still be able to enter Australia but must self-isolate for a fortnight after returning home.

Federal Health Minister Greg Hunt said travel restrictions had been extended by Cabinet's national security committee based on advice from the nation's chief medical officers.

"[The committee] has decided to reaffirm and continue following the medical advice all existing country travel bans," Mr Hunt said.

"The Prime Minister has also referred the question of all travel from Europe from the national security committee to the medical experts at the Australian Health Protection Principles Committee.

"We will continue to follow the medical advice."

It comes hours after United States President Donald Trump announced a 30-day-ban on travel between the US and 26 European countries, excluding the United Kingdom, as cases in the country top 1,000.

No United States ban just yet

When asked why the collective of medical experts had not been asked to consider travel restrictions to the United States, Mr Hunt said the focus was on the areas that had been flagged as "global epicentres" of the virus.

"We look at this at a national level, there are four countries around the world that have been identified as the major centres of transmission," he said.

Earlier, the World Health Organisation declared COVID-19 a pandemic and called on countries to take "urgent and aggressive" action to stop the spread of the virus.

The number of confirmed cases in Australia has continued to rise.

As well as the first diagnosed case in the ACT and a person who attended a music festival in Victoria, Hollywood actor Tom Hanks and his wife have also tested positive for the virus on the Gold Coast.

In a bid to soften the inevitable economic impact of the outbreak, the Federal Government also announced a $17.6 billion stimulus package and conceded it would not deliver a forecast surplus this financial year.

The package includes one-off cash payments of $750 for more than 6 million welfare recipients, tax relief for small businesses and money to help keep apprentices in work.

The virus continues to wreak havoc on the Australian share market with the ASX plunging nearly 8 per cent after the US travel ban announcement.