Nick McBride, who holds the seat of MacKillop in the state's southeast, is reportedly considering his position amid concerns over the handling of COVID-19 border closures and the state's tough exemptions process for people coming from the virus-hit regions of NSW and Victoria.

In his only statement, Mr McBride did not specifically address his plans but rather "noted" the speculation about his future.

He would make no further comment "other than to indicate I will continue to engage with my constituents to ascertain their opinions on a variety of matters".

Quizzed about the apparent rift between the government and the backbencher on Wednesday, Mr Marshall said it was clear a number of MPs, including those in the government, in the opposition and on the crossbenches, were frustrated about issues with the exemptions process.

SA Health is currently dealing with more than 7000 applications to enter the state, prompting long delays on a decision for some people.

The premier said the government was genuinely trying to work through the issues over exemptions, but was not about to just throw the borders open to anyone who applied.

On the subject of Mr McBride's future, he said he talked to the country MP often but was not about to go into details of private discussions.

However, he expressed some confidence in the seat's ongoing representation.

"They elected a Liberal and I think they expect that to continue," the premier said.

Should Mr McBride move to the backbench, the change in numbers in the House of Assembly would further plunge the government into minority rule.

The Liberals hold 23 seats in the lower house with Labor having 19 and five in the hands of independents.

Australian Associated Press