Burberry chief financial officer Stacey Cartwright told the Welsh Affairs Select Committee that the retailer was making a 'manufacturing loss of£1.5 million'. It is set to make savings of£3 million after the move.
Cartwright said the closure of the plant was ultimately 'the most commercially sensible thing to do'.
Production of polo shirts formerly made at the factory will be switched to China when the site closes at the end of this month. Burberry said that overseas production had better manufacturing facilities and lower base costs.
In a paper submitted to the committee, Burberry said that Wales had found it hard to compete with the labour-intensive, value-added economies of Asia.
GMB senior officer Mervyn Burnett said: 'It became very evident to the GMB in the early days that there was no intention from the company's point of view to seriously consider any alternative to the closure plans.'
The GMB has led the extensive campaign to save the plant, including international demonstrations and high-profile support from public figures including Prince Charles and Hollywood actor Rhys Ifans. The union told MPs that there would be little work left in the textile industry in Wales after Burberry leaves.