President Donald Trump tweeted Friday that he has reversed his administration's decision to slap new sanctions on North Korea, with his press secretary explaining that the president "likes" leader Kim Jong Un and doesn't think they're necessary.

It's unclear, however, which sanctions the president was referencing in his tweet, which took Treasury officials by surprise.

"It was announced today by the US Treasury that additional large scale Sanctions would be added to those already existing Sanctions on North Korea," Trump wrote from his private club in Palm Beach, Florida.

"I have today ordered the withdrawal of those additional Sanctions!"

The White House did not immediately respond to questions about which sanctions Trump was referring to, or what large-scale sanctions were poised to be added to existing ones already imposed on North Korea.

North Korea military parade celebrating nation's 70th anniversary Show all 18 1 /18 North Korea military parade celebrating nation's 70th anniversary North Korea military parade celebrating nation's 70th anniversary Participants wave flowers AFP/Getty North Korea military parade celebrating nation's 70th anniversary North Korea's leader Kim Jong Un (R) waves with China's Chairman of the Standing Committee of the National People's Congress Li Zhanshu (L) from a balcony AFP/Getty North Korea military parade celebrating nation's 70th anniversary Airplanes forming the number 70 fly in formation and fire flares AP North Korea military parade celebrating nation's 70th anniversary North Korean performers dance EPA North Korea military parade celebrating nation's 70th anniversary North Korean military officers applaud near portraits of late North Korean leaders Kim Il Sung and Kim Jong Il AP North Korea military parade celebrating nation's 70th anniversary North Korean tanks roll past AP North Korea military parade celebrating nation's 70th anniversary Participants cheer as they take part in a parade for the 70th anniversary of North Korea's founding day in Pyongyang, North Korea, Sunday, Sept. 9, 2018. North Korea staged a major military parade, huge rallies and will revive its iconic mass games on Sunday to mark its 70th anniversary as a nation. (AP Photo/Ng Han Guan) Ng Han Guan AP North Korea military parade celebrating nation's 70th anniversary Korean People's Army (KPA) soldiers take part AFP/Getty North Korea military parade celebrating nation's 70th anniversary Korean People's Army (KPA) soldiers march AFP/Getty North Korea military parade celebrating nation's 70th anniversary Participants march during a mass rally on Kim Il Sung square in Pyongyang AFP/Getty North Korea military parade celebrating nation's 70th anniversary A girl reacts during a parade AP North Korea military parade celebrating nation's 70th anniversary North Korean leader Kim Jong Un, right, reacts as he chats with China's third highest ranking official, Li Zhanshu AP North Korea military parade celebrating nation's 70th anniversary People carry flags in front of statues of North Korea founder Kim Il Sung (L) and late leader Kim Jong Il Reuters North Korea military parade celebrating nation's 70th anniversary Performers take part in a concert at the Pyongyang Indoor Stadium AFP/Getty North Korea military parade celebrating nation's 70th anniversary North Korean artillery roll past AP North Korea military parade celebrating nation's 70th anniversary Students perform Reuters North Korea military parade celebrating nation's 70th anniversary Soldiers march during a military parade Reuters North Korea military parade celebrating nation's 70th anniversary Participants wave flowers AFP/Getty

On Thursday, his administration did sanction two Chinese shipping companies suspected of helping North Korea evade sanctions — the first targeted actions taken against Pyongyang since Trump and Kim met in Hanoi, Vietnam, last month for negotiations about North Korea's nuclear weapons program.

In addition to Trump's talks with North Korea, the US is knee-deep in delicate trade negotiations with China.

A person familiar with the action told The Associated Press that Trump's tweet was not a reversal of existing sanctions, but that the president was talking about not going forward with additional large-scale sanctions on North Korea at this time. The person was not authorised to discuss the president's comments and spoke on condition of anonymity.

It's unclear whether Trump's decision was related to North Korea's move on Friday to abruptly withdraw its staff from a liaison office with South Korea. The development is likely to put a damper on ties between the North and South and further complicate global diplomacy on North Korea's nuclear program. The withdrawal also is seen as a major setback for South Korean President Moon Jae-in, who has sought improved relations with North Korea alongside the nuclear negotiations between the North and the United States.

North Korea said it was withdrawing its staff under instructions from unspecified "higher-level authorities," according to a Unification Ministry statement. It didn't say whether the withdrawal would be temporary or permanent. South Korea called the North's decision regrettable and urged the North to return its staff to the liaison office soon.

'Speed is not that important to me' Kim Jong Un listens as Trump says he's in 'no rush' over North Korea denuclearisation deal

It was the latest example of Trump's governance-by-tweet, which has often sent agency heads scrambling, trying to figure out what he meant and trying to implement policy proclamations that have not gone through traditional vetting processes. That includes when Trump announced, via tweet, that transgender people would no longer be allowed to serve in the military.

And it came hours after Trump made the official announcement that Islamic State-controlled territory in Syria had been reduced to zero from an airport tarmac, using a printed map he held upside-down, instead of a formal statement or ceremony.

His North Korea tweet prompted reporters to bombard officials at the White House National Security Council and Treasury Department with questions. All declined to comment. White House press secretary Sarah Sanders issued a brief statement saying only that Trump "likes Chairman Kim and he doesn't think these sanctions will be necessary."

When the administration announced the sanctions on Thursday against the Chinese shipping companies, administration officials briefed reporters. They said Thursday's sanctions were evidence the U.S. was maintaining pressure on North Korea in an effort to coax its leader to give up his nuclear weapons program.

The Treasury Department sanctioned Dalian Haibo International Freight Co. Ltd. and Liaoning Danxing International Forwarding Co. Ltd. for using deceptive methods to circumvent international and US sanctions and the US commitment to implementing existing U.N. Security Council resolutions.

Calls to the two companies rang without response Friday or were answered by people who immediately hung up the phone.

The Treasury Department, in coordination with the State Department and the US Coast Guard, also updated a North Korea shipping advisory, adding dozens of vessels thought to be doing ship-to-ship transfers with North Korean tankers or exported North Korean coal in violation of sanctions.

Two senior administration officials, who briefed reporters on condition of anonymity to discuss US policy on North Korea, said that illegal ship-to-ship transfers that violate U.S. and international sanctions have increased and that not all countries, including China, are implementing the restrictions. They said the deceptive practices include disabling or manipulating ship identification systems, repainting the names on vessels and falsifying cargo documents.