"Unacceptable pressure by China against Lithuanian diplomats in Beijing," she tweeted on Wednesday. "The United Kingdom stands with Lithuania and my friend foreign minister @glands [Gabrielius Landsbergis] against this coercion".
As China seeks to rename Lithuania's mission in Beijing as the Office of the Charge d'Affaires, Vilnius has summoned Audra Ciapiene, its acting chargé d’affaires, back for consultations.
Lithuania's embassy to China continues its operations remotely from Vilnius and is waiting for Beijing to renew its diplomats' accreditations.
Earlier on Wednesday, the Czech Senate also condemned Beijing's actions against Lithuania as running counter to international law.
Relations between Vilnius and Beijing have been tense lately over Lithuania's deepening ties with Taiwan, which China sees as its territory.
In August, China recalled its ambassador to Vilnius and demanded that Lithuania withdraw its envoy to Beijing. Diana Mickeviciene, the ambassador to China, returned to Vilnius for consultations in early September.
In November, China downgraded diplomatic ties with Lithuania to the level of chargé d’affaires in protest at the opening of the Taiwanese Representative Office in Vilnius.