XIAMEN, June 20 (Xinhua) -- Airlines from both the Chinese mainland and Taiwan have decided to slash cross-Strait airfares by 10 to 15 percent, the mainland's chief aviation official said Sunday, amid expectations the number of mainlanders traveling to Taiwan this year will surge to one million.

Li Jiaxiang, director of the Civil Aviation Administration of China (CAAC), said the price cuts would come into effect in less than six days.

"I talked with heads of all airlines last night and they decided to give 10-15 percent discounts as soon as this forum ends," Li said at the ongoing second Straits Forum held in Xiamen, Fujian Province.

There is no confirmation from the airlines yet, but mainland airlines, overseen by CAAC, are expected to cut prices.

Earlier this month, three Taiwan-based airlines - China Airlines, Eva Airways and TransAsia Airways - said they would cut cross-Strait airfares by 10 to 30 percent starting July 1

The cheapest one-way ticket between Beijing and Taipei for travel in June on Air China, the mainland's flagship carrier, costs around 1,200 yuan (176 U.S. dollars) while a full price ticket costs 3,500 yuan, according to the airline's website.

In addition to cheaper fares, Li said the mainland would build four new airports and renovate four others in the West Strait Economic District -- a mainland region close to Taiwan encompassing 21 cities and several southeast provinces.

Cross-Strait flights will also be increased to 420 per week from the current 380 flights per week, he said.

"Will that be enough? No. There needs to be more flights because about 1 million mainlanders are expected to travel to Taiwan this year and the numbers will continue to grow," Li said.

For decades, travelers had to transfer at a third airport to travel across the Taiwan Strait by air. In 2003, the two sides agreed to operate charter flights during the Spring Festival -- the Chinese equivalent of Christmas.

Regular direct flights across Taiwan Strait have been available since July 2008 when Taiwanese authorities lifted a partial ban on mainland tourists visiting Taiwan.

Wang Yi, head of the State Council's Taiwan Affairs Office, said Sunday about 666,000 mainlanders traveled to Taiwan in the first five months of this year, surging 90 percent from a year earlier. The number of mainland tourists visiting Taiwan, he said, is on track to exceed 1 million by year-end.

Mainland visitors to Taiwan totaled 930,000 in 2009 and the number has grown robustly this year, Wang said.

Echoing Li Jiaxiang's pledges Sunday morning, the GACA announced a series of policies to boost cross-Strait air travel and transportation during a round-table conference held later in the afternoon.

According to the GACA, the mainland's West Strait Economic District and Taiwan would, in the near future, each operate 50 more flights every week across the Taiwan Strait. Among them, 20 would be operated directly between the mainland's Xiamen and Fuzhou in Fujian and Taiwan.

The GACA also pledged to open new air terminals for cross-Strait passenger and cargo transport, and to operate new flight routes between the West Strait Economic District and Taiwan.

Further, Taiwan airplanes could land at the mainland's airports if they encounter unfavorable weather conditions, or other kinds of emergencies, the GACA said, adding that mainland airlines would operate additional flights to Taiwan from Fujian if maritime transport between Xiamen and Taiwan's Kinmen were suspended due to unfavorable weather.

It added that airlines across the Taiwan Strait would increase their own exchanges and cooperation and would jointly train flight crews in the future.

The second Straits Forum, which opened Saturday, will be closed Friday.