Taiwan announced on Tuesday that it will open a de-facto embassy in Lithuania using its colloquial name, prompting China to issue a rebuke.
Taiwan has many de-facto embassies around the world including in the European Union but the vast majority are called "Taipei Representative Offices" as only 15 countries worldwide recognise the island as an independent nation.
China claims the island which is officially known as the Republic of China and rejects any use of the "Taiwan" name on the international stage. It has vowed to retake the island, warning it would use force if necessary.
Joseph Wu, the Taiwanese Foreign Minister, said Lithuania's acceptance to include "Taiwan" in the name of the new de-facto embassy is "very significant."
"Taiwan and Lithuania are like-minded partners bound by an unshakeable belief in the power of freedom and democracy to promote prosperity and build brighter futures for the people," the ministry added.
Vilnius's own representative office in Taiwan will open in the autumn, Wu said.
“I therefore believe that Taiwan and Lithuania’s economic and trade exchanges, cooperation in various fields, as well as the friendships between people will all be enhanced, despite their geographical distance," the minister said.
Beijing's Taiwan Affairs Council said in response that it opposes any country it has diplomatic ties with developing official relations with Taiwan.
"We urge Taiwan to abide by the one-China principle and not to send the wrong signals to Taiwan independence forces," it added.
The American Institute in Taiwan, Washington's de-facto embassy on the island, said in a statement that it "applauds the agreement to establish a Taiwan Office in Lithuania."
"All countries should be free to pursue closer ties and greater cooperation with Taiwan, a leading democracy, a major economy, and a force for good in the world.
"The United States remain committed to supporting Taiwan in a manner consistent with the US "one China" policy as Taiwan strengthens its international partnerships and works to address global challenges, including COVID-19, investment screening, and supply chain resilience," it also said.
Vilnius and Taipei's announcement is the latest in growing signs that some Baltic and central European countries are seeking closer relations with Taiwan, even if that results in angering China.
In May, Lithuania announced it was quitting China's 17+1 cooperation forum with central and eastern European states, calling it "divisive".
It has since pledged to donate some 20,000 coronavirus vaccines to Taiwan and open its own representative office on the island.
Last week, Slovakia also announced it was donating 10,000 vaccines to Taiwan, a gesture of thanks for some 700,000 masks Taipei sent the central European nation at the start of the pandemic.
Politicians in the Czech Republic have also pushed for closer ties with Taiwan.
In 2019, Prague cancelled a sister city agreement with Beijing and signed one with Taipei while a high profile visit to Taiwan last year by Czech senate leader Milos Vystrcil infuriated China.