South Korea wants it, the Trump administration wants it, and Donald Trump himself hinted that China’s Xi Jingping might agree to it. If it has to go through the United Nations Security Council, however, Vladimir Putin says fuhgeddaboudit. The Russian president rejected a direct request for an oil embargo from South Korean president Moon Jae-in, telling him that the humanitarian costs of a total cutoff would be too high for too little gain:

Russian President Vladimir Putin told his South Korean counterpart that cutting off oil exports to North Korea would violate humanitarian norms, South Korea said, signaling that Moscow would likely block U.S.-led efforts to impose an oil embargo on Pyongyang following its sixth nuclear test. …

“We must increase the intensity of U.N. Security Council sanctions,” Mr. Moon told Mr. Putin, according to a readout from South Korea’s presidential office. “It is imperative that we stop the supply of oil to North Korea, and Russia should actively cooperate.”

Mr. Putin batted aside Mr. Moon’s demand, according to the South Korean statement, saying Russia exported very little oil—about 40,000 tons a year—to North Korea. By comparison, China exports roughly 500,000 tons of oil to North Korea each year, according to estimates by the Nautilus Institute for Security and Stability in Berkeley, Calif.

“We are worried that cutting off oil exports will inflict damage on North Korea’s hospitals and on ordinary people,” Mr. Putin said, according to South Korea.

Putin has been trying to dial back the efforts to isolate Kim Jong-un, but to little avail. This confrontation is all the more notable because Moon would normally be more open to Putin’s perspective. He campaigned as a dove, promising re-engagement with Pyongyang, only to see Kim completely ignore him and escalate the situation with further nuclear and missile tests. The political environment in Seoul has changed enough for Moon to go from opposing THAAD deployment to ordering the installation of four more launchers by the end of the week.

Russia holds a veto in the UNSC — and for that matter, so does China. If Putin wants to scotch an oil embargo, he certainly can do so. Thus far, China and Russia have acted in concert to limit the extent of sanctions:

Those threats have prompted both Beijing and Moscow to agree on increasingly tougher sanctions against North Korea, most recently backing a Security Council ban of the country’s coal, iron, iron ore, lead and seafood exports. But the two countries opposed any measures that could destabilize North Korea, a stance Mr. Putin reaffirmed to Mr. Moon on Wednesday.

They said that sanctions had so far done little to stop North Korea from increasing its nuclear and missile capabilities, and that the country remained determined to build a nuclear arsenal despite President Trump’s threatening to rain down “fire and fury” on it.

However, Trump hinted that China might go along with it, and since Kim gets 80% of his oil from Beijing, it might make UNSC action moot:

“We had a very good phone call. It lasted for a long time,” Trump said of his talks with the Chinese leader. “President Xi would like to do something. We’ll see whether or not he can do it. But we will not be putting up with what’s happening in North Korea. I believe that President Xi agrees with me 100 percent. He doesn’t want to see what’s happening there, either.”

Asked if he was considering military action against North Korea, Trump told reporters: “Certainly that’s not our first choice, but we will see what happens.”

A statement posted on state broadcaster China Central Television’s website described Xi telling Trump that China is committed to denuclearizing the Korean Peninsula. But Xi stressed the solution must come through dialogue and peaceful means.

An oil embargo from China would certainly put more pressure on the regime short of war. If Putin’s not on board, though, it would be unusual for China to act. They have insisted on keeping the process of sanctions within the UNSC, where they can control the outcomes with more certainty.

Still, as NBC News points out, they’re getting pretty tired of the drama from Pyongyang:

Officially, China’s position remains the same: The only solution is for both sides to back down, and for dialogue. But editorials in government-controlled newspapers and academic forums, which typically reflect what the leadership here is thinking, there is a noticeable shift in tone and more hawkish viewpoints are emerging.

“It’s time to get rid of all the emotions and be a thorough realist on the North Korea issue,” wrote current affairs commentator Li Fang on the popular WeChat social media platform. “Sanctions are not working, and wars are more terrifying than before… The key is to figure out what to do next.” …

“[North Korea’s] nuclear technology has improved a lot,” said Zhang Liangui, a professor at the Central Party School of the Communist Party of China. “But that’s not the most important… it is that North Korea is determined to go on a nuclear path to oppose global society.”

So far they’re not getting tired enough to take effective action against Kim. The latest nuclear test may force their hand, though. They have over 100 million people living in the region where fallout from this test might land if their underground facility doesn’t properly contain the radioactive material. If they have to take mitigation steps in the region, it could fuel unrest with the regime in Beijing, at which point their concerns over unrest and escapees in North Korea would take a very distant backseat.