Chinese President Xi Jinping on Thursday pledged a “complete reunification” with Taiwan — drawing a strong rebuke from the democratic, self-ruled island, which criticized the Chinese Communist Party’s “dictatorship.”

Taiwan and mainland China are separated by the Taiwan Strait, which is only about 100 miles wide (160 km) at its narrowest point. The ruling Chinese Communist Party in Beijing has never controlled Taiwan, but it claims the island is a runaway province that must one day be reunited with the mainland — by force if necessary.

In a speech to mark the CCP’s 100th year, Xi called “reunification” with Taiwan an “unswerving historical mission” of the party and a “common aspiration” of the Chinese people. The audience erupted in applause in response.

Taiwan’s Mainland Affairs Council lashed out at the CCP in a statement after Xi’s speech. It said the party had achieved economic development in China, but added that it has clamped down on democracy, violated human rights and grown more dictatorial domestically.

“Democracy, freedom, human rights and the rule of law are core principles of Taiwanese society — a major institutional difference from the other side of the strait,” said the Mandarin-language statement, which was translated by CNBC.

The council said the Taiwanese government remains determined to defend the island’s sovereignty and democracy. It added that the Taiwanese people have long rejected the “one China principle” and urged Beijing to abandon military intimidation directed at the island.