Dec 11 (Reuters) - China will strengthen its financial and tax policies to ensure national economic security and ensure fiscal sustainability, Finance Minister Liu Kun said. Liu, in an article republished on the finance ministry’s website dated Friday, also said China would establish a mechanism for local government debt financing to strengthen the prevention of any hidden debt risk. (Reporting by Colin Qian and Kevin Yao; Writing by Se Young Lee; Editing by Jacqueline Wong)