The Avara Foods plant at Abergavenny in Monmouthshire supplies supermarkets and restaurants with chicken and turkey meat.

The firm said the closure by the autumn is the result of rising costs following the Covid-19 pandemic.

The Welsh government called it a "major blow" for workers.

Avara said over the last six months it had looked at several options including different uses for the plant.

"Regretfully this process identified that volumes could be processed more efficiently in other operations and with lower capital investment," a company spokesperson said.

"This has resulted in the proposal to close the Abergavenny site.

"This difficult decision has not been taken lightly and in no way reflects on the hard-working colleagues."

The company said it will begin a period of consultation with the workforce in the coming days.

A Welsh government spokesperson said: "We are aware of Avara's announcement, which will come as a major blow for workers and the community".

"We are in touch with the business to explore options and stand ready to support those impacted by today's news."