The US ambassador to the United Nations has said North Korea's leadership is "begging for war" as she called on the body's Security Council to impose tougher measures against the country following its most powerful nuclear test to date.

At an emergency session in New York, the second in a week, Nikki Haley said Washington will circulate a new sanctions resolution this week, with a view of voting on it next Monday.

The US envoy urged the 15-member group to adopt the strongest possible measures to deter North Korean leader Kim Jong-un.

"War is never something the United States wants," Haley said. "We don't want it now. But our country's patience is not unlimited. We will defend our allies and our territory," she added.

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Haley, who called Pyongyang's latest nuclear test "a slap in the face", also condemned countries trading with North Korea for aiding its "dangerous nuclear intentions".

"The United States will look at every country that does business with North Korea as a country that is giving aid to their reckless and dangerous nuclear intentions," she said.

The Korean Central News Agency (KCNA), the North's state-run agency, has hailed Sunday's test, saying it "marked a very significant occasion in attaining the final goal of completing the state nuclear force".

'Political diplomatic channels'

Meanwhile, China, a top trading partner with North Korea, and Russia called for a peaceful resolution to the crisis at Monday's meeting.

"We strongly urge North Korea to face up to the firm will of the international community on the issue of de-nuclearisation of the (Korean) Peninsula and earnestly abide by the relevant resolutions of the Council," said Liu Jieyi, the Chinese ambassador to the UN.

Jieyi added: "China will never allow chaos and war on the (Korean) Peninsula."

Russia said peace in the region was in jeopardy.

"A comprehensive settlement to the nuclear and other issues plaguing the Korean Peninsula can be arrived at solely through political diplomatic channels," Russia's UN Ambassador Vassily Nebenzia said.

'Bargaining table'

Al Jazeera's Rosiland Jordan, reporting from the UN headquarters in New York, said: "There is a renewed sense of urgency at the Security Council to bring North Korea back to the bargaining table.

"The message which Russia, in particular, was stressing was that there needs to be all efforts to try to talk with Pyongyang and not threaten it," she added.

North Korea has been under UN sanctions since 2006 over its ballistic missile and nuclear programmes.

The council last month imposed new sanctions on the country over two long-range missile launches in July.

The resolution aimed to slash by a third Pyongyang's $3bn annual export revenue by banning exports of coal, iron, lead and seafood.

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Diplomats have said the council could now consider banning Pyongyang's textile exports and the country's national airline, stop supplies of oil to the government and military, prevent North Koreans from working abroad as well as add top officials to a blacklist to subject them to an asset freeze and travel ban.

A resolution needs nine votes in favour and no vetoes by the US, Britain, France, Russia or China to pass.

Typically, China and Russia only view a test of a long-range missile or a nuclear weapon as a trigger for UN sanctions.

China has not publicly said it will back new sanctions, while Russia's Nebenzia said it would consider a US draft resolution, but questioned whether further sanctions would make a difference.

John Ferguson, director of Global Forecasting at the Economist Intelligence Unit, said while there is broad agreement at the council about the seriousness of the problem, there are differences over the level of details.

“Even though no one wants war, the differences in incentives between the US on the one hand, and China and Russia on the other, will stop the full level of sanctions being enforced over the next week,” he told Al Jazeera.

'Existential threat'

Meanwhile, South Korea's air force and army on Monday conducted exercises involving long-range air-to-surface and ballistic missiles in the wake of North Korea's sixth nuclear test, its joint chiefs of staff said in a statement.

In addition to the drill, South Korea will cooperate with the United States and seek to deploy "strategic assets like aircraft carriers and strategic bombers", Jang Kyoung-soo, acting deputy minister of national defence policy, said.

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Al Jazeera's Jordan said both Russia and China have urged the US to rethink its annual pattern of military exercises with South Korea.

"Pyongyang sees those drills as an existential threat and that might be a reason why it is developing a nuclear weapons programme," Jordan said.

Also on Monday, South Korean President Moon Jae-in and his US counterpart, Donald Trump, agreed to scrap a warhead weight limit on Seoul's missiles.