Since the Conservatives became the main opposition at Holyrood, the Scottish Tory leader had been touted by some commentators as a likely leader of the Unionists in the event of another vote.
However, during an interview published yesterday, Davidson ruled out leading the pro-UK side saying it would be inappropriate for the leader of any party to front a campaign.
Davidson said: “I would not myself forward, nor do I think it is appropriate for any party leader to lead the Union case.”
Asked whether she has discussed a pro-Union alliance with Scottish Labour leader Kezia Dugdale, Davidson said: “Of Course I have conversations across party lines about different scenarios.”
In the 2014 referendum former Labour Chancellor Alistair Darling fronted the Better Together campaign.