Merton Council did not prosecute a single landlord for providing unsafe accommodation in the financial year 2014/15, but it says it is working on behalf of residents to help improve rented accommodation.

According to a Freedom of Information request submitted by the London Assembly Liberal Democrat group, Merton was one of 10 boroughs which did not prosecute any landlords last year.

There are about 25,000 households in rented accommodation in the borough.

The council insists it is committed to working to improve rented accommodation without resorting to legal action.

The report also revealed Merton only carried out 179 Housing Health and Safety Rating System (HHSRS) inspections in this time period, meaning only one household for every 140 in rented accommodation were inspected.

HHSRS inspections allow local authorities to identify any risks and hazards in rented accommodation, including examining water, gas and electricity installations, sanitation and drainage, food safety, ventilation and heating.

Merton and Wandsworth London Assembly Liberal Democrat candidate, Adrian Hyyrylainen-Trett, said: “We know that around 60 per cent of renters experience either damp, mould, leaking roofs or windows, electrical hazards, animal infestation or gas leaks – according to housing charity Shelter.

“And yet Merton Council is barely doing anything to help them. It’s clear that this just isn’t a priority for this council.”

The council’s director for community and housing, Simon Williams, said: “We are committed to improving the quality of housing in the private rental sector and have resolved over 400 cases of disrepair in the past 12 months.

“In Merton, most landlords are responsible, but there is a minority who ignore their obligation to maintain their properties. In these cases we do a huge amount of work on behalf of our residents to ensure those more reluctant landlords do meet their responsibilities.

“We work with them to ensure, wherever possible, timely improvement without recourse to lengthy legal proceedings, but they are left in no doubt that if necessary we will prosecute.”