A Russian cargoship detained by South Korea due to its alleged trade links with North Korea has been released.

The 8,700-dwt Sevastopol (built 2001), owned by Gudzon Shipping, was prevented from leaving Busan, but was subsequently released, according to Russian news agency TASS.

"The Korean side did not give any formal explanations for the cause of its detention and release," Gudzon told TASS.

Sevastopol, with a crew of 14 Russian nationals, had called at Busan in mid-August for repairs.

Gudzon was listed among the companies sanctioned by the US on 21 August for violating UN sanctions against North Korea by allegedly participating in ship-to-ship transfers of oil to North Korean-flagged vessels.

Sevastopol was named among the Russian-flagged vessels in which Gudzon has an interest.