The North Korean administration has announced that it will be treating all matters related to the United States under its "wartime law". This comes days after Washington blacklisted dictator Kim Jong Un for human rights abuses, a move which North Korea called an "open declaration of a war".

The announcement on handling US matters under wartime law came on 11 July, hours after North Korea threatened a "physical response" to the US and South Korea deploying the Thaad missile defence system in South Korea.

In addition to implementing wartime law, North Korea has also notified Washington that they are severing the only channel of communication with them, which had been the United Nations (UN) in New York. The handling of American citizens detained by Pyongyang will also be conducted under wartime law.

North Korea's official KCNA news agency stated: "As the first step, we have notified that the New York contact channel that has been the only existing channel of contact will be completely severed. The Republic will handle all matters arising between us and the United States from now on under our wartime laws, and the matters of Americans detained are no exception to this."

Although no details have been specified on how wartime law would impact the two American detainees in North Korea, the state has previously indicated that wartime laws would mean that detainees would no longer be released on humanitarian grounds.

North Korea dictator
Washington blacklisted Kim Jong-un on 6 July for inflicting 'intolerable cruelty and hardship' on masses Ung Yeon-Je/AFP/Getty

The two United States citizens currently detained in North Korea have been named as Otto Warmbier and Kim Dong Chul. Warmbier made international headlines in March after being sentenced to 15 years of hard labour for trying to steal an item with a propaganda slogan on it during a visit to the country.

Washington sanctioned Kim Jong-un on 6 July for inflicting "intolerable cruelty and hardship" on millions of people. It is the first time that the US has directly sanctioned the leader, highlighting sexual abuse, torture, slavery, starvation and executions in prisons.