South Australian construction and engineering company York Civil has entered voluntary administration, but the state's transport minister says work on two major infrastructure projects will go ahead.

The company, which employs about 400 people nationally, is involved in the $800 million Torrens to Torrens Road upgrade and the delay-plagued North Terrace tram extension.

It was announced on Monday that its directors had resolved to appoint Ferrier Hodgson as voluntary administrators, leaving the future of workers and incomplete projects in limbo.

But Transport Minister Stephan Knoll said he had received advice that work would continue on the government contracts.

“Because they’re both under a joint venture arrangement, the other partners to that joint venture take up the responsibility and the liability in relation to the delivery of those projects,” he told reporters.

“We’re hopeful that through that mechanism, that we can ensure that these projects continue to go ahead, but also that the workers that are involved in relation to them can also continue.”

Mr Knoll said the announcement came as a surprise but he did not expect it would result in delays to the projects.

Ferrier Hodgson partner Martin Lewis said the restructuring provider had commenced an urgent assessment of the company’s financial position and the status of its contracts.

“At this stage the company will continue work on the contracts which are subject to the administrators’ review,” he said in a statement.

Mr Lewis said meetings will be held with key stakeholders, including clients, ahead of a creditors’ meeting on August 16.

The company’s staff were told about the decision at a meeting on Monday.

Opposition transport spokesman Tom Koutsantonis blamed the move on a lack of infrastructure spending by the new Liberal government.

“The Liberals cannot wait until the state budget is handed down,” he said.

“New projects are desperately needed to provide a continuous pipeline of work for the construction industry.

“The Liberals’ only commitment is to dig up the tram tracks and install a right-hand turn at the King William Street/North Terrace intersection.”

By Kathryn Bermingham