It’s viewed as the most significant trade deal between Taiwan and the Chinese regime. On Thursday, officials from both countries concluded the terms of the economic cooperation framework agreement— or ECFA. Under the deal, tariffs on more than 800 products would be cut. Banking and service industries would also be opened up. The deal is expected to boost annual two-way trade by about 100 billion U.S. dollars.

For Taiwan, the tariff cuts on 539 products are valued at $13.84 billion. It covers about 15% of Taiwan’s exports to China, and includes petrochemicals and plastics, cars and parts, machines tools and medical equipment. For the Chinese regime, the cuts will amount to only $2.86 billion and covers products including wristwatches, light bulbs and bicycles.

The Taiwan government has been pushing for the deal. It believes closer economic ties with the mainland is the only way to propel the island’s own economy.

But opponents of the deal warn, the ECFA may flood Taiwan with cheap goods from China and create unemployment. They also fear it’s the Chinese regime’s first step towards political takeover of the island.

The Chinese Communist Party views Taiwan as breakaway state, and has vowed to unite the two sides, by force if necessary.

The official signing of the deal will take place on June 29th in the Chinese city of Chongqing.

Taiwan’s main opposition party is planning to hold a protest rally against the ECFA in Taipei this Saturday.