A second council order demanding developers of the Colliers Wood Tower secure and beautify the building voted London’s ugliest was issued on Tuesday.

The Section 215 notice comes into affect amid reports of crumbling masonry and increased crime on the site – including film crews making pornographic movies in the office block’s disused car park.

Developers Criterion must fence off the site, ensure rubble is not visible from the pavement, repair and clean windows, and remove weeds and bushes from the area when the order is implemented on October 18.

Merton Council’s cabinet member for the environment, Councillor Andrew Judge, said: “The tower has been a long standing feature of dereliction for residents and this administration.

“We are doing our utmost to improve the situation and ensure the site looks as good as it can.”

Construction work to rip down the car park and eventually convert the 17-storey monolith into 240 flats begun in May.

But within weeks builders were forced to down tools after problems removing an electricity sub-station. The tower has remained mothballed since, with Criterion anticipated to put in a planning application doubling the project’s scale to 500 flats, later this year.

It was voted the capital’s most hated building in a 2006 BBC poll and two years later a Channel 4 poll placed the tower among the top buildings the British public would most like to see demolished.

But, situated on top of the Tube line, the tower would have to be taken down brick by brick.

Keith Spears, chairman of the Colliers Wood Residents’ Association, said: “It really is disgraceful such a landmark building, which can be seen for miles around, should become a symbol of urban squalor and decay.”