This photo shows night view of Taipei 101, Taiwan, China. (PHOTO / CHINA DAILY)

BEIJING — A Chinese mainland spokesperson on Wednesday stressed that a change in the M503 air route is in line with the common interests of compatriots on both the mainland and Taiwan, aiming to ease traffic congestion and ensure aviation safety.

Chen Binhua, a spokesperson for the State Council Taiwan Affairs Office, said the change will also help improve the operation of cross-Strait flights and better serve personnel travel between the two sides of the Strait.

Relevant authorities in Taiwan had hyped up the move, citing "flight safety" concerns and other ungrounded speculation

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The mainland and Taiwan belong to one China, Chen said. "The Taiwan region is an inalienable part of China's territory. The so-called 'median line' is non-existent," he said.

The Civil Aviation Administration of China (CAAC) announced the change on Tuesday.

However, relevant authorities in Taiwan had hyped up the move, citing "flight safety" concerns and other ungrounded speculation.

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Stressing that the M503 route is a civil aviation route, Chen refuted the comments from the Taiwan side as "completely unwarranted." He also noted that the opening and operation of the route are just normal work in the mainland's civil aviation air space management, and there is no need to consult with the Taiwan side in this regard.