South Korea imposed additional sanctions against North Korea following the United Nations Security Council's toughened regulations to punish the North's Feb. 12 nuclear test, the finance ministry said Sunday.

According to the Ministry of Strategy and Finance, South Korea put three additional North Korean officials and two entities on the blacklist, including officials from a North-based trade firm and a banker.

South Korean citizens and companies making financial transactions with people and firms listed on the list must win prior approval from the Bank of Korea, the country's central bank.

The move came after the U.N. Security Council unanimously adopted a resolution Thursday, which called for the international community to toughen sanctions on North Korea and blacklisted 19 North-based firms and 12 figures.

Under the resolution, U.N. member states are required to inspect all of North Korea's maritime and air cargo "within or transiting through their territory" if it's believed to contain illicit items.

Meanwhile, North Korea drummed up threats of an all-out nuclear war with South Korea and the U.S. on Sunday, a day ahead of a joint military drill by the two allies, which the communist country denounces as targeting the North. (Yonhap News)