The former head of the Catholic Church in Scotland has admitted his sexual conduct had at times "fallen below the standards expected of me".

Cardinal Keith O'Brien resigned last month after the Observer reported allegations of inappropriate behaviour towards three priests and a former priest.

The cardinal initially contested the allegations because of their "anonymous and non-specific nature".

However, in a statement on Sunday he admitted wrongdoing and apologised to the Church and people of Scotland.

"I wish to take this opportunity to admit that there have been times that my sexual conduct has fallen below the standards expected of me as a priest, archbishop and cardinal," he said.

"To those I have offended, I apologise and ask forgiveness.  To the Catholic church and people of Scotland, I also apologise.  I will now spend the rest of my life in retirement.

"I will play no furhter part in the public life of the Catholic church in Scotland."

The cardinal will not be part of the process to elect the successor to Pope Benedict XVI, leaving Britain without representation in the conclave.

Commenting on the revelations, the former Archbishop of Westminster Cardinal Cormac Murphy-O'Connor told the BBC: "The church is composed of saints and sinners.  Sometimes the institution bears responsibility, sometimes it is just the weakness of individuals.  

"The vast majority of priests and bishops are good and faithful men."