The Security Council imposed sanctions after the first two nuclear tests and after the North's rocket launch in December, which was viewed as part of the country's covert program to develop ballistic missiles that can carry nuclear warheads.
The sanctions are aimed at trying to derail the country's rogue nuclear weapons and ballistic missile programs. They bar North Korea from testing or using nuclear or ballistic missile technology, and from importing or exporting material for these programs.
The latest sanctions resolution, adopted in January, again demanded that North Korea abandon its nuclear weapons program and cease missile launches. It slapped sanctions on North Korean companies and government agencies, including its space agency and several individuals.
The diplomats said they did not know what new sanctions would be included in the resolution to be circulated Tuesday.
There has been speculation that a new resolution will strengthen existing sanctions related to North Korea's nuclear and missile programs, toughen financial restrictions and cargo inspections, and add additional companies and individuals to the sanctions list.
Any fresh international sanctions are certain to infuriate North Korea, which has claimed the right to build nuclear weapons to deter alleged U.S. aggression.
After its successful Feb. 12 atomic test, the North's Foreign Ministry said the test was aimed at coping with what it called U.S. nuclear threats and warned that the country would take unspecified "second and third measures of greater intensity" if Washington maintains its hostility.
Pyongyang has blamed Washington for leading efforts to impose the toughened U.N. sanctions for December's rocket launch that it says was only aimed at sending a satellite into space.
On Tuesday, North Korea's military vowed to cancel the 1953 Korean War cease-fire, saying Washington and others are going beyond mere economic sanctions and expanding into blunt aggression and military acts. The Korean People's Army Supreme Command also warned that it will block a communications line at the border village separating the two Koreas.
North Korea and the U.S. are still technically at war because the 1950-53 Korean War ended with an armistice, not a peace treaty. The U.S. deploys about 28,500 troops in South Korea to protect its ally. Pyongyang has long accused Washington and Seoul of plotting to invade the country, though the allies have repeatedly said they have no intentions of attacking the North.
The North's latest nuclear test was seen as a crucial step toward its goal of building a bomb small enough to be fitted on a missile capable of striking the United States. Many outside analysts still believe the North hasn't achieved such a miniaturization technology.