The practice of extra cross-Straits flights during Spring Festival has been popular since direct flights commenced in 2008. The number of the added flights varies from year to year according to the demand shown by flight ticket booking systems.

This year, Chinese mainland airlines planned an additional 509 flights from mainland cities to Taiwan from Feb 2 and March 2 to facilitate the annual rush to and from the island during this year's Spring Festival holiday.

Yet this has met unexpected resistance from the island's civil aviation regulator.

The "civil aeronautics administration" did not approve the applications of 176 flights to be operated by China Eastern Airlines and Xiamen Air, on the grounds of "potential flight safety concerns" for those airlines flying the M503 flight course.

This is a spurious excuse. The M503 flight course, which connects the Pearl River Delta and the Yangtze River Delta, the two most prosperous areas of China, was launched, from north to south only, on March 29, 2015, in order to relieve the air traffic pressure on the old A470 air route along the mainland coast.

Since then more than 100 flights operated by various airlines have used the route each day on average without causing any safety concerns.

Given the rapidly growing number of commercial flights in the region, it was only a matter of time before the south-to-north route would be opened, and this was launched on Jan 8. So far, 27 flights fly a day use the south-to-north route, and given the number of planes flying the other way, the number is sure to increase by a large margin in the foreseeable future.

The Civil Aviation Administration of China opened the new air routes not for political reasons, but to ease the air traffic pressure along its coast.

The M503 air route in both directions is located 12 kilometers to the west of the center line of the Straits in the flight information region of Shanghai, and it is entirely an internal affair of the mainland. The mainland has not the least reason to secure the island’s approval before opening the air route to traffic. The purpose of keeping the island informed ahead of the opening of the air route, which was prepared seven years in advance, was for safety reasons.

Reportedly, the "civil aeronautics administration" has twice demanded the airlines stop flying the south-to-north M503 air route since it was opened on Jan 8, and communicated with the four companies — China Eastern Airlines, Xiamen Air, Cathay Dragon and Hong Kong Airlines — that have flights using the route every day, but none have stopped using the route.

It is clear the rejection of the 176 Spring Festival flights of the first two companies from the mainland is a retaliatory measure out of political pettiness. The island's uncooperativeness is simply absurd, as most of the people affected by the rejection — about 50,000 it is estimated — are from the island. The new air route has obviously made the island's Tsai Ing-wen administration uncomfortable, even though there is no reason why it should. Even Jean Shen, the former head of the "civil aeronautics administration", admitted in an interview with the media that cancelling the 176 flights does no good to the people eager to return to the island for family reunions.

The author is a writer with China Daily.