South Korea has informed Russia it is suspending a trilateral logistics project involving North Korea as part of unilateral sanctions on Pyongyang, government sources said Tuesday.

The Rajin-Khasan project aims to bring Russian coal and other freight to the South via rail and sea links that connect Russia and the two Koreas. It is one of the few projects that Seoul has maintained with the North despite sanctions on most cross-border exchanges.

On Monday, Seoul informed Moscow through diplomatic channels that it will suspend the project under new unilateral sanctions on the North, the sources said, speaking on the condition of anonymity.

Russia reportedly expressed regret at Seoul's decision.

Later Tuesday, Seoul is set to announce a package of new sanctions on the North that is expected to include a ban on the entry of vessels that have visited the North.

The Rajin-Khasan project would fall under that category.

The U.N. Security Council last week adopted a resolution imposing the harshest sanctions yet on North Korea to punish it for its fourth nuclear test in January and long-range rocket launch last month.

Under those measures, several North Korean vessels have reportedly turned back after being denied entry at Russian and Chinese ports, while another ship was impounded in the Philippines last week. (Yonhap)