Clive Fairweather: "Chronic overcrowding"

And he warned that the situation was having an impact on the rehabilitation of offenders.

However, Mr Fairweather said he was encouraged by a fall in the number of deaths in custody, from 25 last year to 16, which represents a five-year low.

In 1999, the chief inspector of prisons said that overcrowding problems would ease early in the new millennium.

But shortly after his comments the Scottish Executive cut �13m from the Scottish Prison Service budget.

Widespread review

This prompted management to close four prisons and initiate a widespread review of the prisons estate.

After almost two years, when prisoner numbers have been rising steadily, no report from the review has been made.

There are now approximately 6,250 prisoners in Scotland in 5,800 places.

Mr Fairweather condemned the delays in refurbishing B Hall at Barlinnie, Scotland's largest prison.

For prisoners and staff, who have had to put up with vile conditions, this has been a pretty scandalous delay.

Clive Fairweather

He said: "For prisoners and staff, who have had to put up with vile conditions, this has been a pretty scandalous delay."

He added that the fact the hall had been empty for around two and a half years, had contributed to the prison being 32% overcrowded.

And he added: "I am concerned about the potential impact of this uncertainty on both the present and future rehabilitation of offenders."

Low Moss near Bishopbriggs in East Dunbartonshire also has severe problems with prisoners housed in wooden huts.

Staff morale

The Scottish Executive insists that prisoner numbers are likely to begin falling soon.

But ministers are not ruling out a programme of privatisation to provide new prisons.

Mr Fairweather said the benefits of such a move were "not clear cut".

He said staff in the Scottish Prison Service (SPS) were "the key issue".

On staff morale, which he said last year was at its lowest for six years, he said: "I would not say that it was worse.

Jim Wallace: "Lasting improvements"

"Overall though, everywhere we go all the staff have said that uncertainty has been the main issue that has come up."

He said industrial relations had been strained, as central management attempted to introduce much needed flexible working practices.

And he added that he hoped the publication of the long-awaited Estates Review should help to address some of the problems facing the SPS.

The report also expressed concern over the impact of illegal drugs, and said that at most local prisons around 80% of admissions are found to have taken illegal drugs at the point of entry.

Justice minister Jim Wallace admitted the prison service had a "difficult" year through uncertainty over the future.

Lasting improvement

But he said progress on the Estates Review in the coming year would remove uncertainty and help staff morale.

Mr Wallace described the review as "crucially important" and called for "serious and practical discussion" when it went out for consultation later this year.

He said new developments at Edinburgh, Polmont and Barlinnie would provide extra accommodation and said there would be a "lasting improvement" from the Estates Review.

Jim Wallace has presided over a period of uncertainty, insecurity and unrest, and it really is time that he started to take some responsibility for the situation

Roseanna Cunningham, SNP

Mr Wallace declared: "I am determined that we should build for the future and put in place improvements that will stand the test of time."

But the Scottish National Party laid the blame for the current predicament in prisons at Mr Wallace's door.

The party's justice spokeswoman, Roseanna Cunningham, said: "He simply insists that numbers are going to start falling soon.

"For two years now, he has been shirking responsibility and that cannot be allowed to continue.

"The prison system in Scotland is not being effectively managed. Jim Wallace has presided over a period of uncertainty, insecurity and unrest, and it really is time that he started to take some responsibility for the situation."

Ms Cunningham said the Estates Review had been "gathering dust" on the minister's desk since December while morale in the service was low.

Bill Aitken: "Building more prisons"

She added: "With millions cut from the prisons' budget and four establishments closed it is hardly surprising that the problem of overcrowding should have reared its head again."

Scottish Conservative justice spokesman Bill Aitken said it was a matter of "great concern" that five prisons were now overcrowded.

"As more prisons become overcrowded, there will be a temptation to go for early release schemes which fail victims, benefit criminals and endanger the public," he said.

"This is a temptation the executive must resist. If sound public order demands the imprisonment of more law breakers, then putting more people behind bars is what we must have the courage to do.

"If that means building more prisons, so be it. Protection of the public must always be our number one priority."