The overcrowded conditions mean Welsh prisons also failed to meet the recommended average of 24 hours a week of purposeful activity for each prisoner.

BBC: Jail crowding worse than ever

Its concerns were raised in a report into "purposeful activity" behind bars.

BBC: Prisoners 'watching too much TV'

However, they said relationships between staff and prisoners remained mutually respectful and there was found to be much more purposeful activity and a greater focus on resettlement.

BBC: NEWS | UK | England | Kent | Prison shows 'marked improvement'