PARIS (Reuters) - French President Francois Hollande will meet Prime Minister Manuel Valls and ministers in charge of economic and transport policy on Monday morning to discuss trainmaker Alstom's sudden decision to scale down its Belfort plant, the president's office said.

Alstom <ALSO.PA> said on Wednesday it planned to stop making trains at Belfort and transfer production to its plant in Reichshoffen in eastern France by the end of 2018. The Belfort site will be refocused on maintenance and repairs.

Valls said on Sunday Alstom's decision was unacceptable.

"Every day, ministers and the President fight for Asltom to win contracts at international and European level. They cannot make decisions in such a way," Valls said in an interview with Europe 1 radio and Itele television on Sunday.

Alstom expects the workload at its French sites to fall by 30 percent by 2018 due to weak orders, with Belfort the most affected because it is specialized in making freight locomotives. Some 400 workers out of Belfort's total 480 would be offered jobs at Alstom's other French sites.

France's former economy minister Emmanuel Macron told Reuters on Saturday the decision was sudden, brutal and unexpected.

(Reporting by Sophie Louet, Maya Nikolaeva and Jean-Baptiste Vey; editing by Susan Thomas)