North Korea threatened to make the United States pay a "due price" on Monday for leading the push for fresh sanctions on Pyongyang.

The UN Security Council is expected to vote on the US led resolution later today, following North Korea's sixth and most powerful nuclear test to date on September 3.

Original wording, including the imposition of an oil embargo on the isolated state and a travel ban on leader Kim Jong-un, has been watered down to appease fellow Security Council members China and Russia, according to diplomats.

Both states, who each have the power to veto any resolution, have been reluctant to pursue tougher penalties on North Korea.

Vladimir Putin, the Russian president, has expressed concern that increasing sanctions on oil would have negative humanitarian impacts for the North Korean people.

"I am concerned cutting off the oil supply to North Korea may cause damage to people in hospitals or other ordinary citizens," he told South Korea's Yonhap news agency on September 6.

China has so far refused to shut off oil supplies to Pyongyang, with Beijing controlling a pipeline that provides approximately 520,000 tonnes of crude oil to its North Korean neighbour each year, according to industry sources.

The final resolution contains reduced sanctions on oil and no longer proposes blacklisting the North Korean leader, a copy obtained by Reuters news agency shows.

An unnamed North Korean foreign ministry spokesman claimed on Monday the US was "going frantic to fabricate the harshest ever 'sanctions resolution' by manipulating the United Nations Security Council".

"In case the US eventually does rig up the illegal and unlawful 'resolution' on harsher sanctions, the DPRK shall make absolutely sure that the U.S. pays due price," the statement, carried by Pyongyang's state media organisation, the Korean Central News Agency (KNCA), added.

READ MORE: North Korea: Kim Jong-un praises nuclear test

Jens Stoltenberg, NATO's secretary-general, condemned North Korea's "reckless behaviour" on Sunday, claiming Kim Jong-un's actions present a global threat that requires a concerted international response.

The NATO chief stressed the need for any resolution to the crisis on the Korean Peninsula to be conflict-free: "We are now totally focused on how we can contribute to a peaceful solution of the conflict," he told the BBC.

Any resolution passed by the Security Council requires nine votes in favour and no veto by either the United States, Britain, Russia, China or France.