Nicola Sturgeon is likely to face a motion of no confidence tomorrow over the Alex Salmond row.
It is understood there will be a 45 minute debate if it goes ahead.
Parliamentary sources had been expecting any vote to take place on Wednesday, but it is believed agreement has been reached for tomorrow.
If this happens, it will take place hours after the publication of a Holyrood Committee's report into the Sturgeon Government's botched probe into Salmond.
Scottish Conservative chief whip Miles Briggs said: "We had hoped to hold the vote on Wednesday but that has now been brought forward to Tuesday.
"The SNP have been complaining that we acted hastily and did not given MSPs time to look at the evidence.
"But pressing ahead on Tuesday make it less likely that MSPs will have time to consider the Salmond Inquiry findings.
"This demonstrates they are in a flap. They clearly expect the Salmond report to be damning, as seen by their increasingly intemperate and disrespectful outbursts towards committee members.
"But no matter what strokes they pull, the evidence is clear that Sturgeon repeatedly mislead parliament and must resign."
