The US Special Representative to Pyongyang made the statement after meeting Japanese foreign ministry officials in Tokyo.
The US may impose unilateral sanctions on North Korea, according to the US special representative for Pyongyang.
“In addition to action in the Security Council, both the US and Japan, together with the Republic of Korea, will be looking at unilateral measures, as well as bilateral measures, as well as possible trilateral cooperation,” Sung Kim told reporters in Tokyo, referring to South Korea by its official name.
Specific details of the US unilateral sanctions have yet to be decided, Kim said.
However, both the US and Japan are looking at “a full range of possibilities, in terms of additional unilateral sanctions that can be implemented,” he added.
— WorldNews_net (@worldnews_net) September 11, 2016
Why is this happening?
The statement comes two days after North Korea carried out its fifth and largest nuclear test in defiance of UN sanctions.
On Friday, North Korea set off its most powerful explosion to date.
Pyongyang claims it has mastered the technique of mounting a warhead on a ballistic missile.
Commentators say this ratchets up the threat that its rivals and the UN have so far been powerless to contain.
What has the UN said?
The UN Security Council denounced North Korea’s decision to carry out the test.
The organisation said it would immediately begin work on a resolution.
The US, Britain and France pushed for the 15-member body to impose new sanctions.
— La France à l'ONU (@franceonu) September 9, 2016
Besides more sanctions, what can be done to thwart North Korea's nuclear ambitions, before it's too late? https://t.co/VwIQj7jdwx
— Brookings (@BrookingsInst) September 9, 2016
“We will be working very closely in the Security Council and beyond to come up with the strongest possible measure against North Korea’s latest actions,” Sung Kim said.