President Donald Trump has designated North Korea a state sponsor of terrorism, allowing the United States to impose additional sanctions and penalties against Pyongyang as it continues to pursue nuclear weapons programs.
The US president, who has traded personal barbs and insults with North Korean leader Kim Jong Un, said the Treasury Department would announce the additional sanctions against North Korea on Tuesday.
The designation came a week after Mr Trump returned from a 12-day, five-nation trip to Asia in which the US president made containing North Korea's nuclear ambitions a centrepiece of his discussions with world leaders.
"Today, the United States is designating North Korea as a state sponsor of terrorism," Mr Trump said on Monday at the White House.
"Should have happened a long time ago, should have happened years ago."
North Korea is pursuing nuclear weapons and missile programs in defiance of UN Security Council sanctions and has made no secret of its plans to develop a missile capable of hitting the US mainland.
It has fired two missiles over Japan.
South Korea's spy agency said on Monday North Korea may conduct additional missile tests this year to polish up its long-range missile technology and ramp up the threat against the US.
Some experts, and US officials speaking privately, have argued that North Korea does not meet the criteria for the designation, which requires evidence that a state has "repeatedly provided support for acts of international terrorism".
Experts also say that the move will be largely symbolic as North Korea is already heavily sanctioned by the US.
Australian Prime Minister Malcolm Turnbull has strongly endorsed Mr Trump's move to designate North Korea a state sponsor of terrorism.
The prime minister said the US president's decision mirrored an international commitment to bring the rogue state to its senses.
"Kim Jong Un runs a global criminal operation from North Korea pedalling arms, pedalling drugs, engaged in cyber-crime and of course threatening the stability of region with his nuclear weapons," Mr Turnbull told reporters in Sydney on Tuesday.
Foreign Affairs Minister Julie Bishop said North Korea posed a threat to Australia's region.
"In the last few years we've seen state-sponsored assassinations, we've seen cyber attacks against the United States and continuing violation of numerous UN security council resolutions prohibiting their ballistic missile and nuclear weapons programs," Ms Bishop told Sky News.
She said the sanctions would place greater restrictions on foreign aid and arms sales to the country.
"The United States is keeping maximum pressure both diplomatic and economic to bring North Korea back to the negotiating table."