South Korea and Japan have imposed unilateral sanctions on North Korea.
The announcement of the sanctions Friday followed Pyongyang's promise to retaliate against new U.N. sanctions imposed earlier this week.
South Korea and Japan already had sanctions in place against North Korea. The new sanctions, however, are mainly symbolic as trade and exchange between the North and its two neighbors are largely non-existent because of existing sanctions, especially those imposed by the United Nations. But North Korea's latest round of nuclear tests has prompted its neighbors to announce the new restrictions.
South Korea is banning the entry of foreign missile and nuclear experts, if their visits to North Korea are deemed to be a threat to South Korea.
Japan said Friday it will not allow ships into the country that have called at ports in North Korea. Japan said it will also freeze the assets of groups and individuals associated with North Korea's nuclear and missile programs.
On Wednesday, the U.N. Security Council unanimously voted to impose a new round of targeted economic sanctions against North Korea for its September 9 nuclear test.
The sanctions take aim at sectors of the defiant nation's economy that generate cash to fund its nuclear and ballistic missile programs, and could cost Pyongyang more than $800 million a year in lost funds – the equivalent of a quarter of its total export revenues.