South Korea and the United States opened a high-level military meeting Tuesday at the Pentagon to discuss North Korea and pending alliance issues on the agenda. The two-day Korea-U.S. Integrated Defense Dialogue (KIDD) comes just ahead of trilateral security talks, also involving Japan, to be held at the Pentagon later this week. "At KIDD, which began this morning, the two sides are discussing issues of mutual security concerns," a Pentagon official told reporters. South Korea's delegation to the talks is led by Deputy Defense Minister Ryu Je-seung. His American counterpart is David Helvey, deputy assistant secretary of defense for East Asia. A South Korean military official here dismissed a view that Helvey's level is relatively low to be Rye's counterpart. "It depends on the format of discussions and agenda times. Mr. Helvey deals with Korea-related issues on a daily basis," the official said. "You don't need to read too much into that."    The biannual KIDD was established in 2011 to serve as the "umbrella framework" for various alliance issues, including extended nuclear deterrence and Seoul's request to further delay the transfer of operational control of its troops in the event of war. The Pentagon said it would release a summary of the results of the consultations on Wednesday. Defense sources said there will likely be no new specific agreement to draw media attention. Meanwhile, the allies plan to hold the Defense Trilateral Talks (DTT) with Japan on Thursday and Friday. Ryu will also participate in that session. In the trilateral session, the U.S. will be represented by Mark Lippert, Defense Secretary Chuck Hagel's chief of staff, while Japan's delegation will be headed by a director general-level official. It's unusual for Lippert to head the U.S. team for the key meetings, given his current position. Lippert, known as a close aide to President Barack Obama, is rumored to be at the top of a shortlist of candidates to become the next U.S. ambassador to South Korea. Having worked as assistant secretary of defense for Asian and Pacific affairs, he is well versed in broader regional security issues, officials said. David Shear, the nominee to become Lippert's successor for the post, has not been confirmed by the Senate yet