UPDATE 1-Peugeot CEO: U.K. plants uncompetitive, open to S. America alliance

Jan 18 (Reuters) - Peugeot SA Chief Executive Carlos Tavares said on Thursday he planned to meet next week with the automaker's UK unions and government officials to discuss the future of Peugeot's Vauxhall plant, where Tavares said production costs are twice those of its plants in France.