Russian President Vladimir Putin said on Monday that Moscow was opposed to any new countries acquiring nuclear weapons, but that the world should talk to North Korea rather than threaten it.
Putin, speaking in Beijing, said nuclear tests of the type that Pyongyang had been carrying out in recent weeks were unacceptable, but that a peaceful solution to rising tensions on the Korean peninsula was needed.
"I want to confirm that we are categorically against the expansion of the club of nuclear powers, including with the Korean Peninsula and North Korea," said Putin, who said any such move would be "harmful and dangerous".
"But at the same time, we understand that what we have observed in the world recently, and specifically flagrant violations of international law and incursions into the territory of foreign states, changes in regime, lead to such kinds of arms races."
Putin did not specify what countries he had in mind, but he has in the past repeatedly criticised the United States for military operations in Iraq, Libya and Syria, and accused it of trying to oust legitimate governments.
"In this connection, we need to act in a joined-up way, (and) strengthen the system of international guarantees with the help of international law and with the help of the UN Charter," said Putin.
"We need to return to dialogue with North Korea and stop scaring it and find ways to resolve these problems peacefully."
The Russian leader said he thought such an approach was possible because of what he called "the positive experience" of holding talks with Pyongyang in the past.
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"If you recall, there was a time when North Korea announced it was suspending this kind of (nuclear) programme, but unfortunately certain participants in the negotiations process did not have enough patience. I think we need to return to this."
Putin said he was briefed by his defence minister after North Korea's latest missile test.
"This missile launch presented no threat to us, but it of course escalates this conflict and there is nothing good about that."
The Russian Defence Ministry said on Sunday that a ballistic missile fired by North Korea had crashed into the Sea of Japan around 500 kilometers (310.69 miles) off the Russian coast.