Foreign Minister Sergey Lavrov says the US should come clean if it is looking for a pretext to destroy rogue state North Korea.
Mr Lavrov on Thursday rejected a US call to cut ties with North Korea in response to the Stalinist regime's launch of an intercontinental ballistic missile.
In some of his most robust comments on the subject to date, Mr Lavrov also flatly rejected a US call to cut ties with Pyongyang over its nuclear and ballistic missile programme and said US policy towards North Korea was deeply flawed.
Tensions on the Korean Peninsula have flared after North Korea said it had successfully tested a new intercontinental ballistic missile on Wednesday in a "breakthrough" that put the US mainland within range of its nuclear weapons.
Russia has condemned the test, like others before it, as "a provocation", but Mr Lavrov said the way the United States was handling the situation was dangerously provocative.
"The latest US actions look designed to deliberately provoke Pyongyang into taking new extreme action," Mr Lavrov told reporters in Belarus, according to a Russian Foreign Ministry transcript.
Mr Lavrov said he was referring to joint US-South Korean military exercises planned for December, which he said US officials had intimated to Russia would not take place until spring to open a window for tensions to be defused.
"We were encouraged by that approach. And then suddenly... they announced large-scale exercises in December. We have the impression that it was all done specially to get Kim Jong Un to 'fly off the handle' and take another reckless step."
The air forces of the United States and South Korea are scheduled to hold a regular joint drill early next month with six US F-22 Raptor stealth fighters taking part.
"The Americans need to explain to us all if they want to find a pretext to destroy North Korea. Let them say it directly ... then we can take a decision about how to react," Mr Lavrov said.
US Ambassador to the United Nations Nikki Haley on Wednesday called for other countries to sever all ties with Pyongyang, including cutting trade links and expelling North Korean workers.
Moscow sells oil products to North Korea and thousands of North Korean workers toil in Russia, sending remittances back to the authorities in Pyongyang.
Mr Lavrov said Haley's call for the world to isolate North Korea was wrong.
"We regard this negatively," Mr Lavrov said.
"We have already said many times that sanctions pressure has exhausted itself."
He also complained the US was "totally ignoring" a UN demand for talks with North Korea.
"I think it's a big mistake," Mr Lavrov said.
Russian Prime Minister Dmitry Medvedev also said US-Russia ties were the worst he could recall, but US President Donald Trump struck him as a friendly person keen to establish positive working contacts with Russia.
Mr Medvedev, who met Trump in Manila this month, said in a televised interview that relations between the two countries were terrible, but that there was still a chance to improve them.
He accused US politicians of playing the "Russia card" to achieve their own aims and influence Mr Trump's attitude towards Russia.
