Prime Minister Scott Morrison has put a $1 billion joint coronavirus funding deal to the states, in what he describes as an "unprecedented" agreement in response to the outbreak.

"I know that's a significant amount but, as we have said to you, and in numerous briefings over

recent weeks, we have to be prepared," Mr Morrison said in Canberra on Friday.

Scott Morrison has offered the states a 50/50 coronavirus funding deal. Credit:Alex Ellinghausen

"We would be very happy to shoulder those costs 50-50 with the states, because of the serious nature and very specific nature of this virus."

The Prime Minister pledged to "immediately put $100 million down as an advance ... to ensure that they are in a position to immediately meet those costs", backdated to January 21.