The Federal Environment Minister has refused to rule out exporting Australian brown coal to developing nations.
So-called "brown coal" is one of the most polluting energy sources, but if there is demand for Australian brown coal, Minister Greg Hunt is not inherently opposed to exploring its export.
Mr Hunt told Tom Elliott the Andrews Government has opened a potential tender which "will ultimately be about exporting coal," potentially including brown coal.
"If that ever comes before me, as a Minister, I'll have to deal with it on the facts," he said on Tuesday.
Mr Hunt also said the Federal government supports new road and rail tunnels for Melbourne, but won't be offering the State government a "blank cheque" to construct it.
"As a general principle, we think that Melbourne needs a cross-city tunnel," Mr Hunt said.
"We want to assess it very carefully.
"Our approach is: what will reduce congestion and improve the quality of life for the people in Melbourne?"