South Australian Premier Jay Weatherill says the federal government should provide at least $375 million to help his state and Victoria respond to the loss of car maker Holden.

The premier’s demand comes after he declared the original offer of $60 million from the federal government, as part of a state-federal package of $100 million, inadequate.

That package included a suggested $8 million from SA, $12 million from Victoria and $20 million from Holden.

But Mr Weatherill says his government is willing to provide at least $50 million and, on that basis, the federal government should be providing about $375 million.

He says the support should come from the money the government saved by slashing assistance to the auto sector.

“We’re not having them making a profit from the closure of Holden,” Mr Weatherill said.

“We want them to quarantine that money and use that for South Australia and Victoria to take the necessary steps to transform their economies.”

The premier hosted two meetings on Monday with industry leaders and major employers in SA, including BHP Billiton and Santos, to brainstorm ideas to overcome the loss of Holden’s car-making operations by the end of 2017.

Mr Weatherill says the loss of Holden is a major challenge for the state, but one it can overcome by helping other companies and industries accelerate their plans for growth.

He says the government will consider providing financial support and assistance with access to credit amid fears the crisis over the loss of Holden may lead to banks refusing to lend to local companies.

“Unless we grasp this as an opportunity and spread confidence about the South Australian economy, we could find us in a scenario where banks choose to stop lending to South Australian businesses,” the premier said.