The United Nations Security Council unanimously adopted a resolution on Wednesday to tighten sanctions on the Democratic People's Republic of Korea (DPRK) in response to its fifth nuclear test in September.

Through the resolution, the 15-member council reaffirmed that the DPRK should not conduct any further nuclear tests, any launches using ballistic missile technology, or any other provocation, according to a UN press release.

A Xinhua News Agency report said that the council decided that the DPRK shall not supply, sell or transfer coal, iron and iron ore from its territory but excluded transactions for livelihood purposes.

The sanctions target revenue sources for DPRK's nuclear or ballistic missile programmes, with the council for the first time imposing a limit on how much coal the DPRK can export per year, according to the UN.

Under the resolution, total exports of coal from the DPRK to all member states should not exceed $400 million or 7.5 million metric tons annually, whichever is lower, beginning Jan 1. For the remainder of this year, the ceiling is $53.4 million, or 1 million metric tons.

In addition, the resolution bans the sale of copper, nickel, silver, zinc and statues from the DPRK.

"I welcome the unanimous adoption of this new resolution. Maintaining such unity is crucial in tackling security challenges on the Korean Peninsula and beyond," said UN Secretary General Ban Ki-moon.

The resolution adopted on Wednesday took nearly three months to materialize, following the nuclear test in September. "The time taken to reach agreement on this resolution vividly illustrates the complex nature of the challenge," Ban said.

The resolution also contains additional measures aimed to further restrict the DPRK's hard currency revenue and the activities of the DPRK's diplomats and other officials.

The DPRK conducted a nuclear warhead explosion test on Sept 9. It was Pyongyang's fifth nuclear test, following the previous one eight months earlier.

"The Chinese government firmly opposes such an act," Liu Jieyi, China's permanent representative to the UN, said

He said the resolution adopted by the Security Council demonstrates the unified stand of the international community against the development by the DPRK of its nuclear and missile programs and for the maintenance of the international nuclear non-proliferation regime.

Liu said that the resolution pointed out that relevant measures are not intended to produce negative consequences on DPRK's humanitarian situation and the livelihood of its people, nor to affect its normal economic and trade activities.

"China urges the parties concerned to effectively implement the relevant provisions of the council resolution in its entirety," he added.

Liu said the top priority for the parties is to resume dialogue and negotiations and relaunch the Six-Party Talks as soon as possible to safeguard the denuclearization process and realize peace and stability on the Korean Peninsula.

"China urges the parties concerned to push forward in parallel the negotiations on the denuclearization on one hand and on the replacement of the armistice with the peace treaty on the other," he said.

Charles Armstrong, a professor of history at Columbia University and an expert on the Korea Peninsula, said these are the strongest sanctions imposed so far, but he is not sure if the sanctions alone could make the DPRK cease its nuclear and missile testing.

"A resolution of the problem can only be reached if there are positive inducements for North Korea to give up or suspend its nuclear program, and that would have to involve dialogue with the US," he said.

"We will have to see what the Trump administration's policy will be toward North Korea, and it will be a few months before the sanctions have any real effect," Armstrong said.

Ted Carpenter, a senior fellow of defense and foreign policy at the Cato Institute, said imposing more sanctions simply continues a strategy that hasn't worked.

"China's willingness to go along with tougher sanctions, though, reflects Beijing's growing impatience with North Korea. It will be interesting to see if Trump adjusts Washington's policy on this issue," he said.

Jon Taylor, a professor at the University of St Thomas in Houston, said the resolution suggests that there is some real consensus among the permanent members of the Security Council to encourage regional stability by halting any further development by the DPRK of its nuclear and missile programs.

He said it demonstrates the council's resolve in upholding the current international nuclear non-proliferation regime. "It underscores the need to be sensitive to any humanitarian concerns that may arise from sanctions by aiming it entirely at the DPRK's military," Taylor said.

Xinhua contributed to the reporting.

chenweihua@chinadailyusa.com