A replacement for Scotland's only all-female jail cannot be "magicked out the air", the Justice Secretary has warned.
Kenny MacAskill spoke out on the issue in response to a report that said Cornton Vale prison, near Stirling, should be demolished.
The Commission on Women Offenders, chaired by former Lord Advocate Dame Elish Angiolini QC, recommended replacing it with a smaller specialist prison for long-term and high-risk prisoners, with regional units to hold short-term and remand prisoners.
Speaking at Holyrood on Thursday, the Justice Secretary said the report did not cause ministers "significant concern", although he accepted that the jail "was not fit for purpose". He said some of the report`s findings were "not news" and revealed there were issues that the government "may have to tweak".
He added: "What I'm making clear in this statement to Parliament is that there is nothing in Dame Elish Angiolini's report that causes us significant concern.
"There's matters in which we may have tweak, and there's issues over just what the timetable can be, but I think we accept that this is a report that is taken in the round, and that is the direction of travel that we will be following.
"I accept the logic and direction intimated by Dame Elish Angiolini, but a prison can't be just magicked out the air, either in terms of the cost of it or in terms of the construction of it."
The minister continued: "But I accept the clear implication that it is not fit for purpose, not withstanding the outstanding service of those who work in it, and that it will ultimately have to go. That's a matter that I will be discussing with the Scottish Prison Service."
The Angiolini commission was set up last year with the aim of finding a better way to treat female criminals and reducing levels of reoffending.
It stated that the number of women in prison has more than doubled over the last decade, although 75% of custodial sentences imposed on females are for six months or less.
Dame Angiolini's recommendations were echoed this week by Brigadier Hugh Monro, the Chief Inspector of Prisons in Scotland, who recommended that Cornton Vale inmates suffering from complex mental health issues should be moved into specialist care facilities.