Russian police on Friday seized a radioactive consignment at Moscow’s Sheremetyevo Airport from a passenger who was about to travel on to Tehran. "Tests showed that the Sodium-22 could only have been obtained as the result of the work of a nuclear reactor," the Russian customs office said in a statement, adding:  "A criminal inquiry has been opened and the materials transferred to prosecutors." Customs was alerted by a warning system at Sheremetyevo ahead of the Moscow to Tehran flight that background radiation in the departures hall was nearly 20 times the norm. A passenger's bag was then searched.

"Eighteen metallic objects of industrial origin were found, packed into individual steel boxes. Tests then found that the objects were in fact the radioactive isotope Sodium-22 that had been machine-produced," the statement said. No further details were immediately available on the consignment or the identity of the passenger who was carrying the materials.

Russia has relatively close ties with Iran and built its first nuclear power station in the southern city of Bushehr. Moscow also delivered the nuclear fuel for the reactor. Moscow has echoed Western concerns about the nature of the Iranian nuclear program but stopped short of publicly accusing Tehran of seeking atomic weapons and always said that the standoff should be solved by diplomacy.

Meanwhile, the US House of Representatives endorsed legislation to expand sanctions against Iran over its nuclear program. The Iran Threat Reduction Act passed by a vote of 410 to 11. The overwhelming votes were largely symbolic, however, as the Senate was not expected to act on the legislation in the few remaining days of the congressional session. The bill focuses on the Iranian Revolutionary Guards Corps and senior Iranian regime officials. It is also meant to close loopholes in energy and financial sanctions and to "counter the regime’s efforts to evade them, including by targeting the Central Bank of Iran."

The government of South Korea announced on Friday that it intends to impose new sanctions on Iran, adding more than 100 names to a financial blacklist of Iranian firms and individuals. Seoul added 99 Iranian firms and six individuals to 24 individuals and 102 Iranian entities already blacklisted in September last year. Those on the blacklist will require approval from South Korea's Central Bank before conducting any foreign currency transactions.