The United States on Friday renewed its confidence in Pakistans nuclear security regime, and said currently it does not have any specific concerns about proliferation from the country. State Department Spokesman Ian Kelly, asked about a report in The Washington Post on reported nuclear cooperation between Pakistan and China about thirty years ago, said he has no comment on the specific claims in the report but said the U.S. is confident about Pakistans nuclear security. Islamabad has rejected claims made in the Post story.Of course, we place a high, may be the highest priority, on the importance of securing nuclear materials. The president (Barack Obama) is committed to a strong non-proliferation regime, the spokesman said at the daily briefing. But talking about this article, this is about something that happened in early 1980s and I dont have any comment on that specific incident. I think, we are always concerned about the possibility of proliferation of nuclear weapons and nuclear materials. We feel confident that the command and control of nuclear weapons in Pakistan is secure. And we dont have any specfic concerns about proliferation per se specifically from Pakisan. Asked if the U.S. raised that issue with China, the spokesman said I dont know, I just dont have that information, it was all 30 years ago, so difficult for me to say.