In a statement released this afternoon, Andrews said he would present his plans to the national cabinet tonight.
"I will inform National Cabinet tonight that Victoria will proceed over the next 48 hours to implement a shutdown of all non-essential activity across our state to combat the spread of Coronavirus," he said.
"This is not something that we do lightly, but it’s clear that if we don’t take this step, more Victorians will contract coronavirus, our hospitals will be overwhelmed and more Victorians will die.
"Victorians will still be able to go to the supermarket, the bank, the pharmacy and other essential stores, like petrol stations and convenience stores. Freight, logistics and home delivery are also considered essential and will remain open.
"I will also inform National Cabinet that school holidays will be brought forward in Victoria, starting on Tuesday 24 March.
"All measures to be implemented by Victoria are consistent with the health advice provided by the Victorian Chief Health Officer.
"The decision whether to re-open schools after the Term 1 holidays will likewise be determined following advice from the Chief Health Officer.
"I will have more to say on these measures tomorrow morning."
NSW premier Gladys Berejiklian said her state would enact their own lockdown period.
"Tonight I will be informing the national cabinet that NSW will proceed to a more comprehensive shutdown of non-essential services. This will take place over the next 48 hours," she said.
"Supermarkets, petrol stations, pharmacies, convenience stores, freight and logistics, and home delivery will be among the many services that will remain open.
"Schools will be open tomorrow, though I will have more to say on this issue in the morning.
"I will update NSW tomorrow morning about the impacts and our plans following the national cabinet."