Story highlights One of the ships was caught smuggling rocket-propelled grenades

North Korea has been accused of evading international sanctions for years

(CNN) The United Nations has slapped a global port ban on four ships for their dealings with North Korea, including one that was caught smuggling 30,000 North Korean-made rocket-propelled grenades in 2016.

Hugh Griffiths, the coordinator for the UN Panel of Experts on North Korea, called the move "swift and decisive."

The port bans were enacted under UN Security Council Resolution 2375, which was passed last month after North Korea test-fired a missile that overflew Japan.

It is the first time the United Nations Security Council 1718 Committee, which oversees sanctions imposed by the Security Council on North Korea, has designated ships for port bans, according to Griffiths.

The UN said the four ships were the Jie Shun, the ship caught smuggling grenades ; the Hao Fan 6, the Petrel 8 and and the Tong San 2.

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