The Church of England has offered an "unreserved apology" for historic cases of child abuse by some members of its clergy, including one priest who was allowed to be a Scout leader.

Officials said it was a matter of "great sorrow and deep regret" and they recognised the harm caused to the victims.

The apology, released on Thursday, coincides with the publication of a report detailing how convicted paedophile Roy Cotton went on to be ordained as a priest.

Cotton was convicted of indecent behaviour with a child in 1954 aged 25 while in training for the priesthood and further damaging allegations were made against him years later.

He was dismissed from theological college, later sacked from a prep school following claims made by boys, and banned by the Scout movement.

But despite his criminal past, he was readmitted to theological training and was ordained in 1966, the same year he was at theological college with his friend Colin Pritchard, who was later jailed for child abuse.

The Scouts agreed to re-license Cotton after he apparently persuaded his diocesan supporters to lobby the movement, the report by independent reviewer Roger Meekings said.

It said: "This was a significant step as it resulted in Cotton receiving 'authorised' and unsupervised access to young people in organised groups. It enabled him to be regarded as an authority figure and a person 'of trust' by parents."

Cotton held several positions as a clergyman, including within the Diocese of Portsmouth, where he was deemed by the bishop of Portsmouth at the time to have been "more sinned against than sinning".

But in 1997, Cotton and Pritchard were arrested by Sussex Police detectives on suspicion of sexually abusing children before being freed on bail.

Cotton retired in 1999 and in the same year the Crown Prosecution Service (CPS) decided to drop its case against the pair. Cotton died in 2006.

Following a separate investigation, Pritchard, who was vicar at St Barnabas Church in Bexhill-on-sea, East Sussex, was jailed for five years at Northampton Crown Court in 2008 after pleading guilty to abusing two children from 1979 to 1983.

The Archbishop of Canterbury banned him from exercising any priestly ministry for life.

The Meekings report said the way Cotton came to be ordained and how he was given the green light as a Scout leader was "fraught with concerns and questions".

Cotton managed to achieve both due to the time that had elapsed since his conviction in 1954 and because senior officers played down the seriousness of it, the report added.

Procedures in sharing information were not followed and the victims were denied the opportunity of being believed, it went on.

Concern was also raised about the issuing of licences to allow both Pritchard and Cotton to continue acting as priests after they retired, particularly as Cotton's conviction from 1954 was known to the church authorities.

A series of recommendations were made, including training senior staff in the diocese in the management of allegations and establish a diocesan child protection management group.

Bishop of Southwell and Nottingham Paul Butler, the joint chair of the Church of England's safeguarding liaison group, said the Meekings report and another, published last year by Baroness Butler-Sloss, were "particularly damning of past safeguarding procedures going back to the 1960s".

He said: "On behalf of the Church, I would like to take the opportunity provided by the publication of these reports to express our own unreserved apology for those cases where we failed to take the action that we should have taken to prevent harm being caused to children and vulnerable adults.

"It is a matter of great sorrow and deep regret for the Church and we recognise the profound and damaging impact on all those affected.

"We are grateful for the personal commitment of many of those who have been affected, to ensuring that the Church faces up to these difficulties.

"This has helped us to become a safer place and to learn more about how to respond well to victims who have the courage to come forward."