Russian authorities have arrested the Ukrainian consul general in St. Petersburg for obtaining "confidential information outside of diplomatic activities." According to the Russian news agency TASS on Saturday, the Ukrainian consul general, Alexander Sosonyuk, was detained after receiving information about a Russian citizen. Russian authorities justified the arrest of Sosonyuk by claiming he obtained confidential information from law enforcement agency databases in the country. Photos show elements of the Russian Federal Security Service during the arrest of the Ukrainian diplomat, marking an unprecedented escalation in the crisis between the two countries. According to TASS, the Ukrainian consul received the confidential information on Friday about a Russian citizen. The Russian Federal Security Service confirmed that "the consul's activities contradict the status of diplomatic work and have a clearly hostile nature towards Moscow." Russian authorities pledged to take necessary measures against the Ukrainian diplomat in accordance with international law. On Friday, Ukraine escalated its position towards Moscow, with Ukrainian President Volodymyr Zelensky advocating for his country’s NATO membership due to the Russian threat, urging Europeans to translate "words into actions." Leaders from Germany, France, and Ukraine have called on Russia to withdraw its forces stationed at the Ukrainian border. Moscow has massed tens of thousands of troops at the borders of this former Soviet republic, which aspires to join NATO. In recent days, Kyiv and Western nations have criticized Moscow for sending troops to the Ukrainian and Crimean borders, with armed clashes occurring almost daily with Russian-backed separatists. U.S. President Joe Biden demanded on Tuesday that his Russian counterpart Vladimir Putin "de-escalate tensions" with Ukraine, joining a group of Western nations that condemned Moscow's troop buildup at the Ukrainian border, which has caused NATO's alarm.