Taiwan authorities bear full responsibility for tensions across the Taiwan Straits over the past two years, a spokesman for the Taiwan Affairs Office of the State Council said at a news conference on Wednesday.

Democratic Progressive Party leader Tsai Ing-wen, who took office on May 20, 2016, has not endorsed the 1992 Consensus, which recognizes that both sides of the Taiwan Straits belong to one China.

Tsai, who has been in office for nearly two years, has slipped in popularity, according to a recent poll conducted by United Daily News, a newspaper in Taiwan.

It found that people's satisfaction with Tsai had declined from 52 percent when she took office to 29 percent recently, and that dissatisfaction has risen from 10 percent to 56 percent.

"Tsai's refusal to recognize the 1992 Consensus has undermined the common political foundation of both sides," the spokesman, An Fengshan, said.

He said that Tsai's administration obstructs and restricts cross-Straits exchanges and cooperation, which damages the common people across the Straits.

The Chinese mainland adheres to the one-China policy, firmly fights any attempt at "Taiwan independence", and continuously promotes economic and cultural exchanges, An said.

This year, the central government issued 31 measures aimed at giving Taiwan residents who reside on the mainland for study or work equal treatment with other mainland residents.

An said on Wednesday that the mainland will not comment on the newspaper poll results because people can draw their own conclusions.

"Our policy toward Taiwan is clear and consistent. We will promote peaceful development of cross-Straits relations and promote peaceful reunification of the country with the aim of enhancing the interests and well-being of the people on both sides of the Straits," he said.

"Taiwan people should realize that the mainland's progress is not a threat or challenge for them but an opportunity. 'Taiwan independence' separatist activities are the real threat for people on the two sides."

"Time will tell," An added. "The achievements we have produced in recent years and the favorable policies toward Taiwan will make more people understand our sincerity."

He added that the mainland will take further action to safeguard national sovereignty and territorial integrity if Taiwan separatists continue to carry out secession activities. The recent live-fire drills carried out by the People's Liberation Army are a clear and strong warning for them, he said.