U.S. Secretary of State Hillary Clinton says Washington remains concerned about North Korean actions and provocations.

Clinton made the remark to reporters after saying she had no comment in response to a question about whether she could confirm North Korea’s involvement in the sinking of South Korea’s “Cheonan” naval ship.

Clinton added, however, that both North Korea and Iran raise concerns for the United States, for NATO allies, and for other countries who see the dangers of proliferation.

Clinton added that the U.S. hopes to see the North return to the six-way nuclear talks that lead to the denuclearization of the Korean Peninsula.