Russia, China bear 'unique responsibility' for N Korean threat: Tillerson

Condemning North Korea's latest ballistic missile launch, US Secretary of State Rex Tillerson said Russia and China bear "unique and special responsibility" for Pyongyang's "relentless" pursuit of nuclear weapons.

He blamed Russia and China for being the "principal economic enablers" of the reclusive regime's nuclear weapons programme, despite it violating multiple UN Security Council resolutions.

Tillerson urged all nations to "take a strong public stance" against North Korea. He asked them to strengthen UN sanctions to ensure North Korea faces "consequences for its relentless pursuit of nuclear weapons and the means to deliver them".

North Korea late yesterday launched its second intercontinental ballistic missile (ICBM) within in a month.

The missile travelled about 1,000 km before splashing down in the Sea of Japan, reports said.

Hours after the launch, North Korean leader Kim Jong Un said it demonstrated his country can hit the US mainland.

The launch came a day after the US Congress voted to impose tougher sanctions against Russia, North Korea and Iran.

Condemning the ICBM launch, Tillerson said that this was in "blatant violation" of UNSC resolutions that reflect the "will of the international community".

"As the principal economic enablers of North Korea's nuclear weapon and ballistic missile development programme, China and Russia bear unique and special responsibility for this growing threat to regional and global stability," he said.

He said the US seeks a peaceful denuclearisation of the Korean peninsula and the end to North Korea's "belligerent actions".

"As we and others have made clear, we will never accept a nuclear-armed North Korea nor abandon our commitment to our allies and partners in the region," he said.

Senator Bob Corker, chairman of the Senate Foreign Relations Committee, asked the US to pursue a "comprehensive approach" to force Pyongyang to back down.

He suggested rigorous enforcement of sanctions, strengthening regional alliances, and expanded deployment of missile defence systems to confront the North Korean threat.

Congressman Mac Thornberry, chairman of the House Armed Services Committee, said another advance for the North's missile programme amplifies the danger to the US homeland and accelerates the need for steps to protect Americans and its allies.

"We need a stronger approach on a faster timeline now," he said.

Senator Joe Donnelly, a ranking member of the Senate Armed Services Subcommittee on Strategic Forces, said: "The administration can and must step up sanctions against China and anyone else who contributes to propping up this dangerous regime".