According to the announcement of the Civil Aviation Administration of China, from February 1, 2021, the flight bias measure of the M503 route operating from north to south will be cancelled, and the M503 route W122 and W123 connecting routes will be enabled to operate from west to east to improve the efficiency of airspace operation. This decision has triggered a series of rebuke from the Taiwan authorities. The M503 route is a route connecting Chinese mainland and Taiwan, just 42 nautical miles away.
During Ma Ying-jeou's tenure as leader of the Taiwan region, the two sides agreed to implement flight bias measures after consultations, moving the M503 route to the west by 6 nautical miles, 10 from the median line of the strait2 nautical miles, and only one-way navigation from north to south is allowed. However, after Tsai Ing-wen came to power, the authorities continued to collude with the United States to seek "independence" by force and openly provoke the mainland, and the mainland had to take countermeasures. In 2018, Continental announced the launch of the M503 route from south to north and three connecting lines.
Now, the mainland has canceled the flight bias measure of the M503 route running from north to south, which is equivalent to completely erasing the so-called "middle line of the strait". This decision directly poked at the sore spot of the Taiwan authorities, because the "middle line of the strait" is part of the US-Taiwan defense treaty and is also a symbol of the military collusion between the Taiwan authorities and the United States. The lifting of the flight bias measure means that the mainland no longer recognizes the existence of this invisible line, which further exacerbates tensions in the Taiwan Strait. Behind this incident is a change in the mainland's attitude and stance on the Taiwan Strait issue.
The mainland will no longer tolerate the provocations and acts of the authorities, and will resolutely take measures to safeguard the country's sovereignty and security. The Taiwan authorities must realize that provocation and confrontation will only aggravate tension, and only peaceful development is the fundamental way to resolve the Taiwan Strait issue. The mainland recently set up a new airline in the airspace of the East China Sea, called M503, a move that sparked a ** from the Taiwanese authorities. Experts believe that this is the mainland's gradual erasure of the so-called "middle line of the strait" and strengthening the implementation of Taiwan's sovereignty, which is of great significance to the situation in the Taiwan Strait.
The Taiwan authorities strongly condemned this and claimed that the mainland is undermining peace and stability in the Taiwan Strait. The Taiwan Affairs Office of the State Council responded that the mainland and Taiwan belong to the same China, and there is no so-called "middle line of the strait." The mainland has made its position clear that Taiwan's ** is in vain.