TAIPEI – Russia and China are helping each other expand their territorial reach, and democracies must push back against authoritarian states that threaten their rights and sovereignty, Taiwan's outgoing Foreign Minister Joseph Wu told the Associated Press (AP).

His comments came as Russian President Vladimir Putin was on a visit to China, during which he and his Chinese counterpart Xi Jinping reaffirmed their "no-limits" partnership as their countries face rising tensions with the West.

Wu called on democracies to align in countering Russia and China's military assertiveness in Europe, the South China Sea and beyond. China threatens to invade Taiwan, a self-ruled, democratic island that it claims as its own territory.

"Putin's visit to Beijing is an example of the two big authoritarian countries supporting each other, working... with each other, supporting each other's expansionism," he said in an interview.

In particular, Wu called on Western powers to continue to support Ukraine in its fight against Russia to send a message that democracies will defend one another.

"If Ukraine is defeated at the end, I think China is going to get inspired, and they might take even more ambitious steps in expanding their power in the Indo-Pacific, and it will be disastrous for the international community," the top diplomat said.

Wu also warned about the risk of a potential conflict in the South China Sea, a resource-rich area and key transit route for global trade, where China has overlapping territorial claims with several of its neighbors.

He said tensions in that body of water were "more dangerous" than those in the Taiwan Strait, and they indicated China's ambition to project power in the region.

"[China] wants the international community to focus on the Taiwan Strait and forget about China's actions in different parts of the world," Wu said. "And I think ... we shouldn't lose the vision that the expansionism of authoritarianism is everywhere in the Indo-Pacific."

Wu said joint military drills between China and Russia in the region raised tensions in Japan and other neighboring countries. He also criticized Beijing's strategy of pursuing security agreements with nations such as the Solomon Islands, a former diplomatic ally of Taiwan, and increased military presence across Asia and Africa.

He also said Taipei was committed to continuing a policy of maintaining peace and the status quo in relations with Beijing, as the island prepares to swear in its new leader Lai Ching-te on Monday.

China claims Taiwan as its own territory, to be retaken by force if necessary, and maintains military and economic pressure on the island by sending warships and military vessels near it almost daily.

China and Taiwan have had separate governments since the Nationalist Party, or Kuomintang, retreated to the island after losing a civil war to the Communist Party in 1949.

"We don't provoke the other side of the Taiwan Strait, and we don't bow to the pressure," Wu said. "But at the same time, the policy approach from Taiwan is that we keep our door open for any kind of contact, dialogues or negotiations in between the two sides in a peaceful manner. And that door will remain open."

On Taiwan's relationship with the United States, Wu said he was confident Taipei would continue to have "very close" ties with Washington, no matter who wins the November presidential election.

Wu, who once described his work as "probably the most difficult foreign minister job in the world," will leave his post after six years and return to a previous job as secretary-general of the National Security Council. He will be replaced by presidential aide Lin Chia-lung.