The bill, to be introduced in November, will propose a change to the release point for short-term prisoners serving sentences of less than four years. At present they are released at the halfway point of their sentence. Under these new proposals they will be released after serving 40 per cent of their sentence, with prisoners serving sentences for domestic abuse or sexual offences excluded from the changes.

Ms Constance said the wellbeing of victims and the safety of communities will be a priority when implementing the measures, and the Scottish government will engage directly with victims organisations.

The proposals, scheduled to come into effect from February next year, would apply to both those currently in prison and those sentenced in future. If backed by Parliament, it is estimated the changes could result in a sustained reduction to the prison population of between 260 and 390.

The proposals in the legislation would also give ministers powers to change the point of release under licence conditions for long-term prisoners serving sentences of four years or more. This follows the recent public consultation on long-term prisoner release, which highlighted various areas requiring more in-depth consideration with partners.

While not currently proposed, contingency planning for the “emergency early release” of short-term prisoners is being undertaken, should it be needed to ensure the health and welfare of prison staff and prisoners during a continuing rise in the prison population.

Ms Constance said: “I am prioritising actions that can deliver a sustained reduction to the prison population. Public safety remains paramount, which is why I am focusing on short-term prisoners only and with built-in exemptions.

“I recognise the concerns that may arise from victims and their families and I am committed to working closely with victim support organisations on key issues.

“The measures I have outlined are necessary to support prisons to continue to function effectively and I remain grateful to Scottish Prison Service staff for their continued resilience. We must ensure that we have a prison estate which houses those who pose a risk to the public and provides the full range of support needed for people to leave on a better path and never turn back.”