Russia opposes international efforts to restrict North Korea's access to oil, President Vladimir Putin announced Wednesday.

Putin's declaration could close off a major avenue for cracking down on North Korea's economy, which U.S. officials believe is necessary to starve the regime of funding for its nuclear weapons program. Western leaders are expected to push for new sanctions at the United Nations Security Council next week, following the largest nuclear weapon test ever by North Korea. But Russia and China both wield veto power and have provided economic lifelines to the regime in recent years.

Putin rooted his defense of North Korea's oil sector in humanitarian goals. "We too are opposing and denouncing North Korea's nuclear development," Putin said Wednesday, per Yonhap News Agency, following a meeting with South Korean President Moon Jae-in. "However, I am concerned cutting off the oil supply to North Korea may cause damage to people in hospitals or other ordinary citizens."

That's the same kind of argument that China has made to defend loopholes in previous sanctions packages, such as the coal crackdown that passed through the U.N. Security Council last winter. Putin's administration also protested when the United States imposed sanctions on Russian companies that have violated the sanctions that the Russian government agreed to, arguing instead that the United States and South Korea should ease tensions by ending military exercises opposed by North Korea.

"[T]he situation on the Korean Peninsula cannot be resolved with sanctions and pressure only," Putin said Wednesday. "We do not need to react emotionally and corner North Korea into a dead end."

Moon, who urged Putin to back the oil sanctions during their private meeting, said talks with North Korea can't take place while the regime takes provocative actions. "I will not avoid any type of dialogue if it can help resolve the North Korean nuclear issue," Moon said this week. "But I believe the current conditions require us to strongly condemn North Korea's dangerous provocations and pressure the North, and that right now is not the time for dialogue."

Secretary of State Rex Tillerson said the United States would not negotiate with North Korea until the regime sends a signal that it is prepared to begin talks that might lead to the end of Pyongyang's weapons program. And he seemed to be moving toward concluding that North Korea had sent such a signal after a two-week period of "no missile launches or provocative acts" in August.

"I am pleased to see that the regime in Pyongyang has certainly demonstrated some level of restraint that we've not seen in the past," Tillerson said Aug. 22. "We hope that this is the beginning of this signal that we've been looking for that they are ready to restrain their level of tensions, they're ready to restrain their provocative acts, and that perhaps we are seeing our pathway to sometime in the near future having some dialogue."

North Korea responded by launching a missile that flew over northern Japan and then testing a nuclear weapon it described as a hydrogen bomb more powerful than any of the five previous nuclear tests.

"I think that North Korea basically has slapped everyone in the face in the international community that has asked them to stop," U.S. Ambassador to the U.N. Nikki Haley said at an emergency Security Council meeting on Monday.