BEIJING - The Chinese mainland and Taiwan will face political topics "sooner or later," Cai Mingzhao, spokesman for the 18th National Congress of the Communist Party of China (CPC), said Wednesday.

"As for the political topics between the two sides, they are objective existence and we will face them sooner or later," Cai said at a press conference on the preparation for the Party congress.

"We hope that both sides work together to create conditions and accumulate consensus to jointly tackle difficult political problems in future," he said.

The spokesman spoke highly of development of cross-Strait ties in recent years.

Since the 17th CPC National Congress in 2007, especially May 2008, cross-Straits ties have witnessed historic transformation and cast off long-term tension and turbulence, he said.

During the period, a series of breakthroughs and major achievements were made, and a new situation of peaceful development emerged in cross-Straits ties, he added.

The past few years were the most peaceful, harmonious and fruitful years in the development of cross-Straits ties. Economic, cultural and social exchanges have developed into an unprecedented level, Cai said.

Practice has proved the CPC Central Committee's guidelines on Taiwan-related work are correct and effective, and the policy consistency will be maintained, Cai said.

On the basis of the 1992 Consensus, the CPC will push forward cross-Straits negotiations with the focus on economic cooperation at the moment. Special efforts are needed to push forward following negotiations of the Economic Cooperation Framework Agreement, so as to make achievements at an early date.

Cai proposed both sides negotiate and make arrangements on cultural, educational, scientific and technological, and environmental exchanges and cooperation.