The federal transport minister said farmers were being forced to detour more than 100 kilometres to find open border crossings.

"I support more fluid crossovers over the river. That really needs to happen," Mr McCormack told ABC radio on Friday.

"We need to do a lot more work today and in the next few hours to make sure that happens."

Melbourne's coronavirus outbreak has sparked hard borders between NSW and Victoria with people needing permission to travel interstate.

Mr McCormack has been in contact with state roads ministers and frustrated mayors about making it easier for farmers to cross.

The issue will be discussed at Friday's national cabinet meeting of federal and state leaders.

The Nationals leader said he understood the medical reasons for lockdowns, but noted regional businesses would feel pain over the decision.

"It was so close to getting the economy back to somewhere where we needed to be," Mr McCormack said.

"Businesses were starting to reopen, people were starting to see customers back, particularly in regional Victoria, and now it's all gone to custard."

Australian Associated Press