SHANGHAI (AP) — The chairman of Taiwan's ruling Nationalist party said Sunday that further cooperation between the Chinese mainland and Taiwan was of utmost importance ahead of expected talks with President Xi Jinping as the former bitter enemies continue their 2-decade-old rapprochement.

"Cross-strait relations are something we all have to face," said Eric Chu, leader of the Nationalists, or Kuomintang. "The 21st century is one of cooperation, not one of confrontation. We must use a healthy attitude, a positive attitude to welcome an era of cross-strait cooperation."

Chu, a likely candidate for the island's presidency in next year's election, spoke at a cross-strait economic and cultural forum in Shanghai attended by representatives from small and medium-sized businesses.

Yu Zhengsheng, chairman of China's top legislative advisory body, told the forum that the key to the peaceful development of cross-strait relations was opposing Taiwan's independence.

Yu also said the forum could discuss ways for Taiwan to participate with the Chinese-led Asian Infrastructure Investment Bank. Taiwan had wanted to join as a charter member but was left off the list by Beijing, which doesn't want the island to use a name in the institution that would suggest it is a country.

Chu, who took over as party leader in January, is expected to hold talks with President and Communist Party Secretary-General Xi Jinping in Beijing Monday.

Chu is the third Nationalist chairman to visit the mainland and the first since 2009.

The Nationalists under Chiang Kai-shek were driven to Taiwan by Mao Zedong's Communists during a civil war in 1949, leading to decades of hostility.

Relations began to warm in the 1990s, partly out of their common opposition to Taiwan's formal independence from China, a position advocated by the self-governing island's main opposition party.

Beijing considers Taiwan to be Chinese territory to be brought under its control by force if necessary.

That prospect has grown increasingly unpopular on the island, especially with younger voters, and opposition to the Nationalists' pro-China policies was seen as a driver behind heavy local electoral defeats for the party last year that led to Taiwanese President Ma Ying-jeou resigning as chairman.