The United States has hinted that a U.N. Security Council response to North Korea’s rocket launch and the seeking of sanctions on Pyongyang are two separate issues.

State Department spokesman Robert Wood told reporters Thursday the U.S. is working within the council to come up with a strong and effective response to the North’s rocket launch. He made the statement after being asked to comment on reports that Russia had made clear its opposition to further sanctions on the North.

Wood said the U.S. is very optimistic and hopeful that the council will come up with an appropriate measure, adding that the form is not as important as a strong and effective response.

On reports that South Korea plans to join the U.S.-led Proliferation Security Initiative soon, Wood only said he’d have to refer to Seoul for more details on the matter.