The Home Office was investigating the possibility of leasing a floating hotel, Robert Maclennan, the party's home affairs spokesman, said.
'The Government has advanced plans to float prison ships again, after a break of around 100 years, to cope with the gross overcrowding in our jails. This is a Dickensian touch to their Victorian attitude to crime and punishment,' he said.
The Home Office was investigating a plan by the Liverpool-based shipping firm Bibby Line to convert a floating hotel moored in Sweden. 'The company tells me that it is proposing to lease the vessel and the Home Office is now paving the way for the scheme in the Criminal Justice Bill, which will give the Home Secretary powers to declare any floating vessel to be a prison,' Mr Maclennan said.
'Prison ships are still used in parts of the world. Being surrounded by water is not a guarantee of security, however. A breakout by prisoners from one such vessel in the Philippines led to an attempted coup. The escaping man took 12 of his jailers with him to try and overthrow the government.'
The Prison Service said that alternatives were being looked at should overcrowding arise. But figures showed a decline in the prison population since the autumn, with 46,911 prisoners in custody with accommodation available for 47,181.