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There is no comparison between China's claim to Taiwan and the crisis in Ukraine, Beijing's foreign minister said on Monday.
Wang Yi said Taiwan was a domestic matter for China, while Ukraine was a dispute between two countries.
"We have seen that some people emphasise the principle of sovereignty on the Ukraine issue, but continue to undermine China's sovereignty and territorial integrity on the Taiwan issue. This is a naked double standard," he said, in apparent reference to the US.
Mr Wang was speaking at his annual news conference on the sidelines of China's annual parliament meeting.
China claims the island as its own territory and insists that Taiwan has never been an independent country.
It held military exercises near the island in recent months, in what was described by Taiwan as a threat to it.
Taiwan says only the Taiwanese people can choose their future.
China's President Xi Jinping said last year he wanted to realise peaceful "reunification" with Taiwan.
Washington is Taiwan's most important international backer and arms supplier, a frequent source of friction in Sino-US relations.
Mr Wang said tensions were Taiwan's fault for its refusal to accept that it is part of China, a refusal which will "ruin Taiwan's future".
In his reaction to the Chinese minister, Taiwan's Mainland Affairs Council said in a statement it was China's military threats, diplomatic pressure and attempts to "assault" the island that were the cause of tensions.
'China's most strategic partner'
The Chinese foreign minister also described Russia as "China's most important strategic partner".
“No matter how perilous the international landscape, we will maintain our strategic focus and promote the development of a comprehensive China-Russia partnership in the new era,” Mr Wang told reporters.
China has not condemned Russia's invasion of Ukraine and rejected joining the US and the EU in imposing sanctions on Moscow. It, however, expressed its concerns about the growing humanitarian crisis and called for a political settlement of the conflict.
During an hour-long phone conversation with US Secretary of State Antony Blinken on Saturday, Mr Wang said China opposes any moves that “add fuel to the flames” in Ukraine.
He said the US and Europe should pay attention to the negative impact of Nato’s eastward expansion on Russia’s security.
In his press conference, Mr Wang said ties with Moscow constituted “one of the most crucial bilateral relationships in the world”.
“The friendship between the two peoples is ironclad,” he added.
Much attention has been paid to a meeting between Mr Xi and Russian President Vladimir Putin in Beijing on February 4, after which a joint statement was issued, affirming “strong mutual support for the protection of their core interests”.
Russia endorsed China’s view of self-governing Taiwan as an “inalienable part of China, and opposes any forms of independence of Taiwan".
China and Russia have increasingly aligned their foreign policies. Their armies have carried out several joint exercises in the past.
Agencies contributed to this report.