The United States supports UN Security Council discussion of North Korea's alleged crimes against humanity, a senior official said.
But Robert King, US special envoy for North Korean human rights issues, expressed concern over whether the council had time to take up the issue.
Details of systematic executions, torture, rape and mass starvation inflicted by the Pyongyang government were laid out in a report issued by a UN commission of inquiry last month.
The commission, led by a retired Australian judge, urged the Security Council to consider the report and refer North Korea to the International Criminal Court.
Tomorrow, the UN's top rights body, based in Geneva, will consider its recommendations, including empowering the United Nations to keep gathering evidence - a much less contentious step.
China, the North's only major ally, is almost certain to oppose a referral to the Security Council, where it wields a veto.
King said the US was discussing the commission's recommendations internally and with other countries, including the question of referral to the court.
He said Japan and Europe had been drafting a resolution on North Korea that the 47-member council would vote on by the end of this week, but the text had not yet been finalised.
The question of a referral was one of balancing the "pros and cons", including whether the council had time to take up the issue, and if it did, what action it would take, he said.
"We have been very supportive of the commission of inquiry. If it can be worked to have this debated, discussed in the Security Council, we certainly would be supportive of doing that," King said. "It's a question of what's going on right now at the Security Council. It's fairly fully occupied trying to deal with issues like Ukraine … Can we get it on the agenda and can we have a productive discussion? We are hopeful we can."