Russia has denounced North Korea's nuclear ambitions as a "direct threat" to the country.
"It is not only a ballistic missile defence system - it has real function," said Deputy Defence Minister Alexander Fomin.
"That is why it is alarming. And it is a direct threat to Russia. We are convinced that it will increase the tensions of the region. That is our principle position."
Mr Fomin spoke at the Shangri-La Dialogue, an international security conference in Singapore attended by defence ministers and experts from 39 countries, including US Defence Secretary Jim Mattis.
Russia borders North Korea and saw one of Pyongyang's missiles land close to its waters. But it differs from the US and its allies on how to rein in the North's rapidly escalating nuclear and ballistic missile program.
Backing fresh sanctions on North Korea, Russia's deputy UN ambassador Vladimir Safronkov stressed in June that "the choice here has to be made in favour of using diplomatic tools to the maximum extent possible".
But Mr Fomin had similar sentiments. "Economical restrictions should be a kind of tool to invoke North Korea to a peaceful process of resolving the dispute and conflict, and not to once again deteriorate the economic solution in North Korea," he said.
Addressing the South China Sea conflict, Mr Fomin chose his words carefully. "All states involved in territorial disagreements in the South China Sea need to adhere to the principle of the non-use of force," he said.
China - a Russian ally - has pitted itself against its smaller neighbours in claiming disputed islands, coral reefs and lagoons in the South China Sea.