Russia's security agency said on Saturday it arrested the Ukrainian consul general in Saint Petersburg over spying allegations.
According to the Federal Security Service (FSB), Alexander Sosonyuk was detained "red-handed" at a meeting with a Russian citizen while trying to get classified information, including data from Russia's law enforcement agencies and the FSB databases.
"These activities are incompatible with the status of a diplomatic employee and are clearly hostile to the Russian Federation," the FSB said.
It added that his case will be considered in accordance with the norms of international legislation.
The Vienna Convention provides for immunity to diplomats in countries of their work, but they can be deprived of the right to stay in a country in case of violation of local law or hostile actions.
The convention also stipulates that the receiving state may at any time notify the sending state that the head of mission or other diplomatic official is declared persona non grata and that his presence in the country is unacceptable.
The detention comes amid heightened border tensions between Ukraine and Russia.
