Kieve, April 18 : In a retaliatory move, the Ukrainian Foreign Ministry has asked a Russian diplomat in Kiev to leave the country within 72 hours starting from April 19 in response to Moscow's expulsion of a Ukrainian consul. In a statement on Saturday, the Foreign Ministry said it strongly protests against Russia's "illegal" detention of an employee of the Consulate General of Ukraine in St. Petersburg on April 16 and completely rejects the accusations made against the consular officer, reports Xinhua news agency. "In response to this provocation, the senior diplomat of the Russian Embassy in Kyiv must leave the territory of Ukraine within 72 hours, starting from April 19," a statement read. Earlier on Saturday, the Russian Federal Security Service (FSB) reported Ukrainian consul Oleksandr Sosoniuk was detained while he was trying "to obtain classified information from the databases of the Russian law enforcement agencies and the FSB" in St. Petersburg. "These activities are incompatible with the status of a diplomatic worker and are clearly hostile towards the Russian Federation. Measures in accordance with international law will be taken against the foreign diplomat," the FSB said. The Russian Foreign Ministry said on Saturday that Sosoniuk's stay in Russia is "undesirable" and that he has been advised to leave the country within 72 hours starting from April 19. /IANS