(Expands, adds context)
VILNIUS, Aug 18 (Reuters) - Lithuania's foreign ministry said on Thursday it had issued a formal protest to China over sanctions against the Baltic country's deputy transport minister, calling for the restrictions to be rescinded.
China's foreign ministry said on Friday it had imposed sanctions on Lithuanian Deputy Transport and Communications Minister Agne Vaiciukeviciute for visiting Taiwan.
Lithuania's ministry demanded that China rescind the move, and resume cooperation with Lithuania in the field of transport which was revoked after the visit.
"China's unilateral decision is unjustified, it violates international law and Lithuania's sovereignty", it said in a statement.
China claims self-ruled Taiwan as its territory and is against foreign politicians visiting the island. Taiwan rejects China's claim.
China has downgraded diplomatic ties with Lithuania and pressured multinationals to sever links with the Baltic nation of 2.8 million people after it allowed Taiwan to open a de facto embassy in Vilnius.
The EU launched a challenge at the WTO in January accusing China of discriminatory trade practices against Lithuania that it says threaten the integrity of the single market.
The United States, Britain, Australia and Taiwan have backed the challenge. (Reporting by Andrius Sytas in Vilnius, editing by Terje Solsvik and Bernadette Baum)