Lebanon has requested Interpol issue international arrest warrants for both the captain and owner of the ship which is believed to have caused the 4 August Beirut blast, Agence France Presse (AFP) reported.
The Moldavan-flagged MS Rhosus is widely understood to have brought nearly 3,000 tonnes of ammonium nitrate into Beirut port in 2013, where it stayed until it exploded two months ago, killing nearly 200 and injuring thousands more.
Lead investigating judge Fadi Sawwan has also issued two arrest warrants, in absentia, for the two individuals, according to a judicial source cited by AFP.
The ship's captain is understood to be Boris Prokoshev, a Russian national. However, the identity of the second man being sought by Sawwan was not immediately clear due to a dispute over who was the owner of the Rhosus at the time of its final journey.
Russian national Igor Grechuskin was widely reported as the owner of the Rhosus in the days after the explosion, and he faced questioning by Cypriot police over the incident.
However, a joint investigation by the Organised Crime and Corruption Reporting Project (OOCRP) and Der Spiegel later uncovered that the true owner of the ship was Charalambos Manoli, a Cypriot shipping magnate.
Manoli denied the claim, saying Grechuskin had bought the ship prior to its fateful final journey, though the OCCRP report refuted this version of events.
The Rhosus made an unscheduled stop in Beirut on its journey from Georgia to Mozambique, reportedly to collect cargo on route to Jordan, to help raise sufficient funds to pay for the vessel's passage through the Suez Canal.
The ship was later impounded after Beirut port authorities deemed it unseaworthy and a Lebanese company filed a lawsuit against the vessel's owner.
The Rhosus and its crew of three Russians and one Ukrainian were then abandoned in Beirut and the cargo offloaded and stored improperly in the port's warehouse 12. The crew were eventually evacuated, and the vessel later sank in Beirut port, several years after its initial arrival.
The tonnes of ammonium nitrate remained in the port's warehouse until sparks caused the substance to ignite and explode on 4 August.
More than two dozen people, mainly officials and port authorities, have been arrested in Sawwan's probe into the cause of the blast. According to AFP sources, a delegation of Sawwan's team visited Cyprus last month to question the owner of the shop, sparking authorities to issue arrest warrants.