"We have lifted the ban on the vessel as in our probe we didn't found any violations committed by the ship. The cargo ship is now allowed to leave (South Korea) any time," ministry spokesman Noh Kyu-duk said over the phone.

    The ministry said that "putting on hold" the ship's departure is different from its detainment, which is a measure taken in cases where a vessel is confirmed to have engaged in illicit activities, such as any violation of UN Security Council resolutions.      

    On Monday, Russia summoned Seoul's ambassador to Moscow, Woo Yoon-keun, in protest against the "illegal" seizure and demanded its immediate release.

    It's one of six Russian-flagged vessels blacklisted by the US government in August as part of efforts to foil North Korea's clandestine trade that breaches the UN sanctions.

    "The government has been conducting an investigation with regard to the Sevastopol," the spokesman said at a press briefing earlier in the day.

    He cited the dilemma of balancing South Korea's relations with Russia and its commitment to the faithful implementation of UN sanctions. (Yonhap)