TAIPEI/BEIJING -- Chinese mainland and Taiwanese negotiators on Thursday signed two cross-Straits agreements on investment protection and promotion and customs cooperation, signaling a major step forward in the institutionalization of cross-Straits economic cooperation.

The two pacts were signed by Chen Yunlin, president of the Chinese mainland-based Association for Relations Across the Taiwan Straits, and Chiang Pin-kung, chairman of the Taiwan-based Straits Exchange Foundation, during their eighth round of talks held since 2008.

In the long-awaited investment protection and promotion agreement, the two sides agreed to offer "just and fair treatment" to their respective investors and investment projects, as well as provide them full protection and security, by gradually lifting restrictions and introducing a detailed dispute settlement mechanism for cross-Straits investments.

The agreement also highlights an affiliated common understanding on personal freedom and safety issues related to cross-Straits investment.

According to the document, after detaining a Taiwanese resident who works for a Taiwan-invested company on the mainland, mainland police will be required to inform his or her relatives of the detainment within 24 hours. If the relatives do not live in the mainland, police should inform the detainee's employer. The same rules will apply to Taiwanese police.

In terms of customs cooperation, the mainland and Taiwan will work to simplify customs procedures, improve the efficiency of customs clearance and enhance the effective supervision of cargo for cross-Straits trade.

Both sides will gradually work out a scheme to recognize Authorized Economic Operators on each side to facilitate their goods' customs clearance, and they will conduct exchanges on the application of radio frequency identification in customs supervision and step up sharing customs information.

The signing of the two agreements has been widely hailed as a key move in terms of carrying forward the cross-Straits negotiations following the signing of the landmark cross-Straits Economic Cooperation Framework Agreement in 2010 and of deepening the economic cooperation between the mainland and Taiwan.

In his inaugural speech at Thursday's talks with Chiang, Chen said the investment protection agreement will serve as a "realistic solution" to problems regarding the protection of investors' rights and interests during two-way investment.

"It will offer systematic protection for investors on both sides," he said. "Besides offering protection for (direct) investors in a common manner, the agreement clearly prescribes protection for Taiwanese investors who inject capital into the mainland via a third place."

Chiang said the agreements will also be meaningful in shoring up the competitiveness of the mainland and Taiwanese businesses in economic globalization.

As the first protocol reached since the ECFA, the investment protection agreement highlights the characteristics of cross-Straits relations, which will help create a better investment environment and promote economic prosperity across the Strait, according to Shen Danyang, spokesman for the Ministry of Commerce.

The Chinese mainland is Taiwan's biggest trade partner and export market. The execution of the early harvest program under the ECFA since January 2011 has allowed goods from both sides to enjoy either reduced or zero tariffs, saving businesses on both sides hundreds of millions of US dollars, especially those in Taiwan.

Industrial participants and analysts believe that the two fresh agreements, among the total of 18 cross-Straits pacts signed since 2008, when the ARATS-SEF negotiations resumed after a nine-year suspension, will further the trade and economic cooperation and personnel and cultural exchanges between the mainland and Taiwan and help develop a win-win situation.

In an interview with Xinhua, Chang Pen-Tsao, chairman of Taiwan's general chamber of commerce, termed the investment protection agreement a "breakthrough," in which the "expanded" definition of investors will mean a great many Taiwanese business people who invest on the mainland via third places will be protected by the pact.

He added that it is especially significant that the common understanding on personal freedom and safety issues has been adopted.

"Those arrangements are unconventional for an ordinary investment agreement," said Zhang Guanhua, deputy director of the Beijing-based Institute of Taiwan Studies under the Chinese Academy of Social Sciences, adding that the move fully embodied the sincerity of the mainland.

Li Dongsheng, chairman and CEO of TCL Corporation, told Xinhua that by improving the mechanism for investors' rights and interests on both sides, the investment protection pact meets the need for deepening cross-Straits economic cooperation and promoting two-way investment.

The conclusion of the investment protection agreement after the tough negotiation process demonstrated that both sides held a realistic yet future-oriented attitude, said Sheng Jiuyuan, executive director of the Shanghai-based Pudong Research Center on Taiwan Economics.

During the Chen-Chiang talks on Thursday, both sides also reviewed the implementation of the ECFA and increasingly closer cross-Straits economic and cultural ties since 2008.

They agreed to hasten negotiations for signing agreements on service trade, goods trade and disputes settlement, which has been a major task facing the ARATS and the SEF.

Both sides agreed to strive to reach a service trade agreement soon and step up exchanges in professional areas, including those regarding air pollution and earthquake monitoring, among others.

Furthermore, ARATS and SEF leaders also exchanged opinions on establishing offices on both sides, urging related assessment and planning work to be conducted first.