MOSCOW, September 13. /TASS/. Moscow and Washington believe there is no alternative to solving the North Korean nuclear issue by diplomatic means, Russia’s Foreign Ministry said after a phone conversation between the Russian and US diplomats on Tuesday.

The conversation between Russian Deputy Foreign Minister Igor Morgulov and Sung Kim, the US State Department's special representative for North Korea policy, was held at the initiative of the US side.

"Both sides expressed serious concerns over another nuclear test carried out by North Korea," the ministry said. "They stressed that there is no alternative to the political and diplomatic solution to the nuclear problem of the Korean Peninsula through holding talks."

"The determination was confirmed to continue contacts at the UN Security Council with the goal of developing an adequate international response to Pyongyang’s actions," the ministry said.

North Korea successfully carried out its fifth nuclear test on September 9. Pyongyang said it confirmed that a nuclear warhead can be mounted on the country’s ballistic rockets.

This was North Korea’s most powerful device to date, with a yield of 10 kilotonnes, South Korea’s Ministry of National Defense said. North Korea has previously conducted four nuclear tests: in 2006, in 2009, in 2013 and in January 2016.