Russian President Vladimir Putin chose not to return a North Korean general's salute during a summit with North Korean leader Kim Jong Un on Friday, Korean state TV footage shows.

When President Donald Trump was faced with same situation at the June 2018 summit in Singapore, he returned the salute.

At the time, critics shook their heads at Trump, and a retired US Army general said Trump just saluted a "regime of terror, murder, and unspeakable horror."

The White House responded by saying it was "common courtesy" to return a salute.

During the summit, Putin and Kim discussed nuclear disarmament and bilateral ties , but neither side announced any action.

, but neither side announced any action. Visit Business Insider's homepage for more stories.

Russian President Vladimir Putin refused to return a salute from one of North Korea's top generals on Friday, taking the opposite approach of the one President Donald Trump took when faced with the same situation.

Putin was seen in a 50-minute documentary broadcast on Monday on Korean state TV shaking hands with a line of dignitaries after a summit with North Korean leader Kim Jon Un in Vladivostok, Russia.

When a senior general chose to salute Putin, the president smiled, did not return the salute, and instead offered a handshake.

The moment was recorded and posted on Twitter by BBC Monitoring, which reports on foreign media.

Although recent US presidents have regularly saluted members of the armed forces, it is relatively rare for other world leaders to salute anybody while not wearing a military uniform. In this encounter, Putin appears to be sticking to that tradition.

On June 12, 2018, Trump met with Kim in Singapore and was offered a salute by a general in a very similar scene. Unlike Putin, Trump returned the gesture.

Trump saluting a North Korean general on June 12, 2018. KCNA

Read more: Kim Jong Un rode his bulletproof armored train from North Korea to Russia's extreme east for his first meeting with Vladimir Putin

Both Putin and Trump are commanders in chief of their nations' militaries.

Approaches to saluting officers in foreign militaries vary, but critics in the US said that Trump's mark of apparent respect to the North Korean general gave Kim's harsh and repressive regime a legitimacy it does not deserve.

Here is a video of the encounter:

Major Gen. Paul Eaton, a retired US Army general, released a statement on Trump's salute, saying: "It is wholly inappropriate for the commander in chief of our armed forces to salute the military of our adversary, especially one which is responsible for a regime of terror, murder and unspeakable horror against its own people."

Kim Jong Un and Trump in Singapore on June 12, 2018. Associated Press

The White House rebutted the criticism. Press secretary Sarah Huckabee Sanders said: "It's a common courtesy when a military official from another government salutes, that you return that."

Read more: 8 ways Trump could offend the Queen when they finally meet

Others suggested that Trump had not broken any protocol but had allowed himself to be used for propaganda by the North Koreans, who would enjoy the image of their military being afforded respect by a US president.

Matt Lewis, a political commentator for The Daily Beast and CNN chalked Trump's actions up to well-meaning ignorance.

"Reciprocity is a natural instinct. If someone salutes you, your instinct is (probably) to return that salute," he said. "This is to say Trump wasn't being malicious; he was being played."

Trump and Kim on February 28, 2019, in Hanoi, Vietnam. Evan Vucci/AP Photo

During the summit on Friday, Putin and Kim discussed nuclear disarmament and bilateral ties between Russia and North Korea.

Neither side announced it was taking any action after the summit.

The documentary made no mention of nuclear weapons or disarmament but described the trip in these terms, according to South Korea's Yonhap News Agency: