The Air Products announcement was the latest hammer blow to the region
Rising unemployment in north east Wales needs to be "urgently addressed", Wrexham Council's leader has said.
Aled Roberts, reacting to the closure of Air Products at Acrefair with 200 jobs lost, said the council would contact the Welsh Assembly Government.
The Unite union is to seek a rescue package for the area following news of the Air Products closure.
It is the latest blow to the area which has seen hundreds of manufacturing jobs cut in months.
Aled Roberts said he believed American-owned Air Products had already decided to close Acrefair despite counter-proposals from workers and Unite.
Wrexham has been heavily reliant on manufacturing, more so than almost any area of the UK and the figures are giving rise to concern
Aled Roberts, Wrexham Council
He added: "It was always made clear that the decision would be taken in the United States.
"But when multi national companies make this kind of announcement, it's very rare that they go back on it during the consultation process."
He said the council would support workers in putting their case to the UK government for a package of financial aid to try to save the factory, or to explore the option of a buy-out.
The council would also be contacting the assembly government to raise its concerns over rising unemployment in the Wrexham area, particularly a steep rise among 18-25 year olds.
He said: "Wrexham has been heavily reliant on manufacturing, more so than almost any area of the UK and the figures are giving rise to concern.
Air Products supplies items such as gas used in the welding process
"Here in north east Wales we've always been referred to as the 'powerhouse' and left to get on with it, but there are now serious issues that need to be addressed urgently."
In recent months, more than 150 job cuts have been announced at JCB in Wrexham, and a decision has been made to close the Flexsys chemical plant with the loss of 163 jobs.
In Denbighshire last month, it was announced the Indesit washing machine factory, employing 302 people, will also close.
Following the latest announcement at Air Products, the Unite union said it would be pushing the UK government for a rescue package to try and maintain manufacturing at Acrefair.
The plant, which opened in 1950, employs 140 craftsmen and 50 in management and administration.
Spokesman Graham Rogers said Air Products workers were "despondent" and "very critical" of the decision to close the plant and switch production to China.
He said many workers had helped train staff in China - only to be told that is where the work is being switched to.
He added: "We were given assurances that if we came to the party... and we supported the project in China, it would have no effect as far as the Acrefair site.
"That's the annoying part."
Fiona Sinclair-Davies, who's husband Dai works as an engineer at Acrefair, runs a Facebook support group and said she will continue to campaign for the Acrefair workers.
She said it was "ridiculous" that her husband had worked in China for a month to train staff, adding: "It's such a destruction for it to close, and we wanted the local community to come in and outsiders to realise you can not keep taking work away from Wales, from our country."
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