The Opposition fears funding for South Australia's regional roads is an afterthought for the Malinauskas Labor Government, with initiatives in this area making up a tiny six per cent of the total roads budget.

Of the $7.83 billion budgeted for roads over the next four years just $467.4 million is going towards those in our regions - a tiny slice of the pie.

Shadow Minister for Regional Roads Adrian Pederick said proper investment in country roads is vital to support communities, improve economic outcomes and help save lives.

"Peter Malinauskas is leaving regional roads to crumble by shunning rural investment," Mr Pederick said. 

"Around 30 per cent of South Australians live in country areas, but only six per cent of the roads budget is going towards the regions and that's not good enough. 

"Approximately half of the budgeted funds will be spent on the South Eastern Freeway and the Adelaide Hills Productivity and Road Safety Package, leaving just $242.4 million for the many thousands of kilometres of country roads across the state. 

"The regions are the backbone of our economy and home to many major transport routes. There's also a high concentration of vehicle accidents in country areas, so proper investment in our regional roads is essential. 

"The former Liberal Government made a good start on repairing more than a decade of Labor's neglect on regional roads, upgrading more than 4,800 kilometres.

"Thankfully, work on the Strzelecki Track - a project initiated by the former Liberal Government - is ongoing and continues to be funded. This will create better access to our critical oil and gas industry in the Cooper Basin as well as being a valuable stock route for pastoralists. 

"Minister for Regional Roads Geoff Brock might say the 'days of city-centric politics need to end' but his actions certainly aren't showing that's the case when it comes to this year's State Budget.

"It's not good enough for Peter Malinauskas to leave our regional roads in his rear-view mirror."