Shadow treasurer Jim Chalmers has urged the government to only allow workers to access their superannuation if they lose their job due to the coronavirus pandemic as a "last resort".

The government is due to release details of its $66 billion stimulus package on Sunday, amid claims it could include measures to allow early access to super to help struggling workers.

Shadow treasurer Jim Chalmers. Credit:Alex Ellinghausen

Dr Chalmers but did not say whether or not Labor would look to block any legislation introduced should the measure be proposed but told ABC Insiders it would not have been his chosen path and there were "already hardship provisions" in super.

"Firstly, we don't know if it needs legislation. There's a very strong prospect that it doesn't and that it won't be a parliamentary vote," he said.