China on Wednesday said it was not aware of the reported intrusion by its troops into Arunachal Pradesh in December, emphasising that the so-called state in India's northeast does not exist.According to media reports, Chinese soldiers with road-building machines entered up to 200 metres into Arunachal Pradesh last year."First of all, on border issues with India, China is clear and consistent. We never acknowledge the existence of so-called Arunachal Pradesh," said Foreign Ministry spokesperson Geng Shuang."For the specific situation you mentioned, I am not aware of it," he said.China claims India's Arunachal Pradesh as its own and calls it Southern Tibet. The northeast state lies in the eastern sector of the 3,448 km-long un-demarcated Sino-Indian border."I want to mention that between China and India, there is a well-developed mechanism on border related affairs. Through this mechanism, Beijing and New Delhi can manage their border affairs," Geng said."Also, maintaining peace and stability on border areas suits the interests of both China and India."China-India ties took a nosedive last year when their armies were locked in over a two-month face-off at Doklam in the Sikkim section of the border.The crisis was resolved in August and both sides at their 20th round of border talks in December pledged to maintain peace and tranquillity along the disputed boundary.