An artwork in the centre of Newport that depicts the 1839 Chartist revolt in the city is being demolished.
The 35m mural, created in 1978 using 200,000 pieces of tile and glass, is being torn down as part of a shopping centre development.
The move has “shocked and deeply saddened” campaign group The Twentieth Century Society, which had submitted a listing application for the mural to Cadw, the Welsh Government’s heritage body, in July this year.
The application was turned down in September, as the mural fell short of the criteria to be listed at the national level on grounds of its lack of special architectural interest.
A local petition in support of saving the mural attracted more than 4,000 signatures, and a protest in the city centre against the destruction of the piece had been planned for this weekend.
Henrietta Billings, senior conservation adviser at The Twentieth Century Society, which campaigns for the conservation of the best 20th-century architecture, said: “The speed at which the demolition has begun ahead of the public demonstration this weekend is startling.
“Future generations will look back on this day with great regret.
“The mural is without doubt one of Wales’ best pieces of postwar public art.”
A spokesperson for Newport City Council said the council “recognises how important the Chartist history is to Newport”.
“The mural is a modern day depiction of an historical event that happened in Newport and has served to remind us of Newport’s past, but we must now focus on Newport’s future,” said the spokesperson.
“The current Chartist mural is in a very precarious position, as it is attached to the wall of the multi-storey car park which is extremely unsafe.
“The council has had to take immediate action with regards to pre-demolition preparations and safety precautions.
“Major demolition work will be starting at the end of this month.
“The council is committed to commissioning an alternative solution to commemorate the Chartist movement and will be consulting with the public on the nature of this different form of celebration shortly.”
The Chartist mural was constructed in 1979 by Kenneth Budd, a renowned figure in postwar mosaics.
It depicts the 1839 Chartist uprising in the city – that year, on 4 November, protesters discontented with their impoverished living standards and divided over how best to achieve the passing into law of the six points of The People’s Charter, grouped outside the Westgate Hotel.
When they tried to enter, soldiers lying in wait fired shots, killing 22 marchers and wounding many more. The remaining Chartists then retreated.
Leading participants, including John Frost, were sentenced to be hung, drawn and quartered, but after protests from all over the country the sentence was reduced to transportation.
The mural was deliberately positioned in a city centre subway off John Frost Square to commemorate the event and act as a memorial to the Chartists.
It is made of ceramic tile and Venetian glass; materials that give the mural 3D qualities.