GLAXOSMITHKLINE HAS ANNOUNCED that it is set to close its manufacturing plant in Sligo by 2021, with 165 jobs set to be lost.

Workers at the Stiefel Laboratories site, which manufactures skincare products, were told today of the plans to close the site.

In a statement, GSK said that while the Sligo plant had delivered “significant improvements in cost and efficiency” in recent years, demand for the products made on the site had not grown in line with expectations.

It said a number of alternatives had been considered for the site, but “none of them were considered feasible without significant further investment”.

GSK added that it would aim to support its workers, their families and the local region “through this difficult period”.

The company had previously announced plans to close the Stiefel site in Sligo, but a €10 million investment from the IDA saved it in 2012.

Stiefel Laboratories first opened in Sligo in 1975, before being taken over by GSK under a decade ago.

Responding to the news, Fine Gael TD Tony McLoughlin called it a “very disappointing announcement for Sligo”.

He said the government would make every State support available to workers at the plant, and this news comes against the backdrop of an “extremely positive” trend in overall job creation in the county.

It is understood that the pharma giant’s other Irish sites – in Cork, Dungarvan and Dublin -  will not be affected by the closure in Sligo.