SEOUL -- North Korea has demolished a major monument in its capital that symbolized the goal of reconciliation with South Korea on the orders of leader Kim Jong Un, who last week called South Korea a "primary foe" and said unification was no longer possible.

Satellite imagery of Pyongyang on Tuesday showed that the monument, an arch symbolizing hopes for Korean reunification which was completed after a landmark inter-Korea summit in 2000, was no longer there, according to a report by NK News, an online outlet that monitors North Korea.

Reuters could not independently confirm that the monument, known informally as the Arch of Reunification, had been demolished.

Kim called the monument an "eyesore" in a speech at the Supreme People's Assembly on Jan. 15, where he ordered that the constitution be amended to say the South was a "primary foe and invariable principal enemy," official media said.

Tensions have spiked on the Korean peninsula following intensifying military maneuvers by the South Korean and U.S. militaries in response to weapons testing by the North, which said it was readying for a "nuclear war" with its enemies.

The arch, formally known as the Monument to the Three Charters for National Reunification, stood 30 metres tall and was symbolic of the three charters, which were self-reliance, peace and national cooperation, according to South Korean government records.

Asked if North Korea appeared to be changing its posture on conflict with the South, White House spokesperson John Kirby told reporters on Tuesday, "We're watching this very, very closely."

He added: "I would just tell you that we remain confident that the defensive posture that we're maintaining on the peninsula is appropriate to the risk."

South Korean President Yoon Suk Yeol, who took office in 2022, has taken a hard line against the North, calling for immediate and tough responses to North Korea's military actions that have raised tensions on the Korean peninsula.

North Korea has vowed to "wipe out" South Korea if attacked by the South and U.S. forces. Late last year, the North declared as no longer valid a key agreement signed with the South in 2018 aimed at de-escalating military tensions.

Following Kim's speech last week, the North's assembly abolished key government agencies that have been instrumental to decades of exchanges with Seoul.

Additional reporting by Jeff Mason and Trevor Hunnicutt in Washington; Editing by Bernadette Baum, Mark Porter and Leslie Adler