BEIJING, Jan. 31 (Xinhua) -- A Chinese mainland spokesperson Wednesday denounced Taiwan's move to obstruct extra holiday flights across the Taiwan Strait, saying it was a grave deviation from the humanitarian needs of millions of families and tourists.

"The unreasonable practice of the Taiwan authority impairs the trips of tens of thousands of tourists, the get-together of many families and the feelings of compatriots across the Strait," said Ma Xiaoguang, spokesperson with the State Council Taiwan Affairs Office at a press conference.

Citing security concerns regarding the M503 route, the Taiwan authority refused to approve 176 additional cross-Strait flights operated by China Eastern Airlines and Xiamen Airlines, for the most important family gathering festival in China.

The decision is expected to make it difficult for around 50,000 people to return home during the holiday. Additional cross-Strait flights for the festival have been a regular practice since 2008 when direct flights between the two sides began.

"The Taiwan authority linked two totally irrelevant issues together and penalized Taiwanese living on the mainland," Ma said. "It has gone to the length of taking residents and business people from Taiwan as hostages in retaliation against mainland airlines."

"Such a move has seriously compromised the welfare of people on both sides, particularly Taiwanese people," Ma said, stressing that the air route and those connected to it were safe.

"The mainland will make every effort to assist Taiwan compatriots in their trip home," Ma said, adding that Fujian Province had increased the frequency of passenger liners across the Strait.

A leading official from the International Air Transport Association (IATA) spoke in support of the Chinese mainland operating the M503 route to ease traffic congestion, earlier this month.

The M503 route, which has been used since March 2015, is not a new route. Its position and design have been approved by the International Civil Aviation Organization, the IATA official said.

Airlines from China's Hong Kong and Macao special administrative regions and southeast Asian countries began flying north to south on the M503 route in March 2015.

The Taiwan aviation authority, however, expressed concern over the start of the south-to-north operation on the route on Jan. 4 this year.

Chen Chien-ming, a Taiwanese living in Shanghai, has been forced into a difficult situation by the sudden change of policy.

He received a final confirmation from China Eastern Airlines Tuesday that the ticket he booked for a trip from Shanghai to Taipei on Feb. 10, a week ahead of Spring Festival, was canceled.

Chen's only option is to try other airlines, but prices have soared compared to a month ago when he booked. Return tickets across the Strait now costs more than 7,000 yuan (1,111 U.S. dollars), matching to the cost from China to Europe.

"The shortage of flights caused price hike. This is all because of the Taiwan authority's decision," Chen told Xinhua. "This is so unreasonable."

Besides the cost, Chen also has a limited choice of flight time. "Most tickets I can get now are at odd hours, for example midnight," he said. "All we want is to go home. The [Taiwan] authority never considers our needs."