The Australian government has scrapped childcare fees to help parents who keep working through the coronavirus crisis, as Scott Morrison warned the nation on Thursday to brace for at least six months of disruption to society.

In another day of fast-moving developments, Australia’s death toll from Covid-19 rose to 24, Western Australia announced it would shut its border this weekend, and medical teams started to check the health of crew members aboard the Ruby Princess cruise ship off the coast of Sydney.

The childcare sector had been pleading for a financial lifeline to avoid staff cuts and even closures, as an increasing number of parents have been pulling their children out of care over the past few weeks.

Morrison said the entire funding system would be overhauled from next week to ensure parents who needed to keep sending their children to childcare did not have to pay any fees. The prime minister said he did not want parents to have to choose between feeding their children and having their children cared for and educated.

“This virus is going to take enough from Australians without putting Australian parents in that position,” he said.

From Monday, the government will start making payments to childcare centres at the rate of about 50% of the usual fees but based on attendance numbers in late February, before the numbers of children attending plummeted.

The government estimates these payments will be worth $1.6bn over the coming three months. Centres may also be eligible to claim the new wage subsidies of $1,500 per worker a fortnight.

In return for receiving the new government payments, childcare services will be prohibited from charging families a fee – including an out-of-pocket or gap fee – and must stay open unless forced to shut on public health advice. Centres have been told to prioritise care to essential workers, vulnerable and disadvantaged children and previously enrolled children.

The education minister, Dan Tehan, said the government was “turning off” the complex old funding system because it was “drafted for a pre-pandemic time”. The government insists the free childcare plan is temporary.

Early Childhood Australia, a peak body, said the announcement “tackles most of the big issues that services and families have been grappling with over the past month”.

But Goodstart Early Learning, the nation’s largest provider with 665 centres, issued a statement saying the plan did not offer “any comfort for the 3,000 casual educators we had to stand down last week”. It warned that it would not be able to keep its centre open unless the government guaranteed it access to the jobkeeper payment scheme.

Speaking to the Seven Network, Morrison indicated that schools across Australia would reopen after the Easter holiday period, but said there would be a protracted period when many students would be participating through e-learning, while those who had to attend in person could do so.

In the latest sign of intensifying restrictions to stop the spread of the virus, the WA premier, Mark McGowan, announced that his state would close its border from Sunday night, with several limited exemptions, such as for health and freight purposes.

“In effect, we will be turning Western Australia into an island within an island – our own country,” he said.

Morrison declined to be specific when asked on Thursday when Australia’s international border might reopen or other strict restrictions on public gatherings might be lifted. But he took the opportunity to urge Australia to “stay together” and brace for the long haul, ahead of another meeting of the national cabinet on Friday.

“There is a new normal here in Australia and it’s one that we now need to get used to and settle into for that haul over the next six months,” Morrison said. “That is something that will go against the grain for so many, but we adapt. We can change the way we live, but it doesn’t change who we are.”

Morrison became emotional as he recounted being told stories by his grandmother about what they used to do as a family to get through the Great Depression.

While the prime minister said it was a great comfort to him that his family had joined him in Canberra, he added that it was difficult to “imagine the world on the other side of this and to give your family some positive and encouraging news about how amazing Australia is and how we all come out of this”.

Parliament will return on Wednesday next week to pass the $130bn wages subsidy package, which aims to help up to 6m Australians who face an uncertain economic future, the latest in a series of stimulus and support measures. But calls are growing for greater parliamentary oversight of the extraordinary measures being rolled out at a rapid rate to address the Covid-19 pandemic.

On Thursday, Labor and the Greens both backed the idea of a parliamentary committee to scrutinise the government’s response, following the lead of New Zealand.

Labor wants the parliament to return not just to pass the third economic support package but as a means of restoring legislative oversight, as most decisions to tackle the public health crisis are occurring through unchecked executive actions.

The opposition leader, Anthony Albanese, told ABC Radio either a Senate committee or a joint select committee “should be established to provide that oversight, both in terms of the departmental responses but also to hear from people about where there are gaps in the system”.

Later, on Sky News, Albanese noted that Labor had supported and improved the first two tranches of economic support, but warned the government that “bipartisanship does not mean silence”.

However, Morrison played down the suggestion that parliament should do more than “continue to do its job, as it is called on to do, in terms of passing legislation”.

“The difficulty in calling the parliament together is a practical one, frankly,” he said. “We have got people coming to Canberra and moving to other parts of the country. As we need to call the parliament together, we will, and it will continue to do its job.

“Equally, our parliamentarians, while they may not be meeting here, I know they are working incredibly hard in their communities.”

Morrison suggested MPs were busy helping their constituents contend with challenges posed by the current crisis and “frankly, they have got a bigger job to do out there in their communities at the moment than they would have here [in Canberra]”.

On Thursday the Greens leader, Adam Bandt, wrote to Morrison asking for the creation of a joint committee with a non-government chair and 11 members: four from the Liberal and National parties, three from Labor, one Green and three crossbench MPs or senators.

The Centre Alliance senator Rex Patrick who supports the plan, said a joint committee would “allow both houses to provide oversight, but a fallback position would be to have the Senate initiate a committee” – a threat to proceed with or without government support.