WASHINGTON — The Obama administration is facing another difficult choice with Iran: As Tehran takes apart much of its nuclear infrastructure to win sanctions relief, how vocally should the White House condemn Iranian violations of United Nations resolutions on other issues?

Based on the first responses Tuesday to reports that Iran had conducted yet another launch of a medium-range ballistic missile, the answer appears to be not very loudly.

Samantha Power, the United States ambassador to the United Nations, said that Washington was “conducting a serious review of the reported incident.” She said that if the review determined that the test occurred, the United States would take the issue up with the Security Council.

American officials did announce some sanctions on Tuesday for ballistic missile tests — but they were against North Korea, for violating Security Council resolutions by launching short- and medium-range missiles in tests last year.