The corpse, the tenant's former lodger, was found by council workers on a sofa in the lounge after neighbours reported a foul smell emanating from the Bristol flat.

The deceased man's identity has not been released but police said he is believed to be in his 70s. Bristol Coroner's Court confirmed that an inquest will open later.

The tenant who remained living in the property was initially arrested in connection with the discovery but police are no longer treating the death as suspicious.

It is believed the tenant, who is also in his 70s, failed to report the death because he suffers from severe mental health problems.

A spokesman for Avon and Somerset Police said the body was discovered by council workers on January 30.

He said: "We're investigating the death of a man in his 70s. The body was discovered by council employees on January 30. It's important to stress we did arrest a man in connection with the incident but we're no longer treating the death as suspicious."

Bristol City Council has launched an internal inquiry to establish how the corpse went unnoticed for so long. A spokesman for the council said it is believed the body was there for at least eight years.

He said: "We were alerted to the body after we received reports of a smell. We are shocked and concerned by this discovery and are carrying out an urgent internal review of the circumstances of the tenant.

"A police investigation is ongoing, and it would be inappropriate to comment further while this is taking place."