China has officially downgraded diplomatic ties with Lithuania in protest, the foreign ministry in Beijing said Sunday, after Taiwan established a de facto embassy in Vilnius.
Lithuania allowing Taipei to open an office using the name Taiwan was a significant diplomatic departure that defied a pressure campaign by Beijing.
China baulks at any official use of the word "Taiwan", lest it lend a sense of international legitimacy to the island -- which it considers a part of its territory to be taken one day.
"The Chinese government had to lower diplomatic relations between the two countries... to safeguard its sovereignty and the basic norms of international relations," the ministry said in a statement announcing the downgrade to the charge d'affaires level.
"The Lithuanian government must bear all consequences that arise from this."
It added that Lithuania had "abandoned the political commitment made upon the establishment of diplomatic relations" with China.
It was a reference to the "One China" policy, under which countries officially recognise Beijing over Taipei.
Lithuania's foreign ministry on Sunday said it "regrets" China's decision to downgrade ties.
"Lithuania reaffirms its adherence to the 'One China' policy, but at the same time has the right to expand cooperation with Taiwan," the ministry said in a statement.
Taiwan announced in July that it would open the office, its first new diplomatic outpost in Europe in 18 years.
That prompted a fierce rebuke from China. It withdrew its ambassador from Lithuania and demanded Vilnius do the same, which it eventually did.
China also halted freight trains to Lithuania and stopped issuing food export permits.