The leader of Taiwan's new ruling party promised to seek peace and economic engagement with China ahead of his departure Monday on a trip to the mainland to meet President Hu Jintao. Wu Poh-hsiung, chairman of the Nationalist Party, is making the six-day trip at the invitation of China. It's the first mainland visit by the head of a ruling Taiwanese party. The ice between the sides was first broken in 2005 when then-Chairman Lien Chan of the Nationalist Party - the biggest opposition party at the time - made a historic visit to China. China demands unification with the self-governed island and has threatened to attack if Taiwan seeks a permanent break. Most Taiwanese reject unification, fearing it would deprive them of their freedoms and compromise their economic prosperity.