(Adds quotes, details, background, byline) By Arshad Mohammed WASHINGTON, Jan 5 (Reuters) - The United States warned North Korea on Friday there would be "severe consequences" to the diplomatic effort to end Pyongyang's atomic ambitions if it conducted a second nuclear test. State Department spokesman Sean McCormack also said the six-party talks designed to get North Korea to give up its pursuit of nuclear weapons in exchange for aid and security guarantees could resume later this month. McCormack made the remarks as U.S. officials tried to play down reports suggesting North Korea, which carried out its first nuclear test on Oct. 9, might be making preparations for another test. "If you did have another test of a nuclear device, that would have severe consequences for the viability of that political-diplomatic process -- why would they take such a step at this time?" State Department spokesman Sean McCormack told reporters. South Korean officials said activity had been spotted near a suspected nuclear test site in North Korea but there was no evidence to suggest Pyongyang was about to test another atomic device. The South Korean officials spoke ahead of a meeting between U.S. Secretary of State Condoleezza Rice and South Korean Foreign Minister Song Min-soon that was expected to focus on North Korea and the six-party talks. The six, which include the two Koreas, China, Japan, Russia and the United States, made no progress in their last round of talks last month in efforts to have the North scrap its nuclear weapons plans in exchange for aid and security guarantees. McCormack declined comment on whether U.S. intelligence has detected fresh activity at suspected North Korean nuclear sites but said Washington, based on its political assessments, had "no indication" North Korea intended to conduct a new test. "(We) have no indication that they are planning to conduct any kind of test," said another U.S. official who asked not to be named because of the sensitive nature of information about North Korea. While effectively warning North Korea against a fresh test, McCormack also said "the signals are" that six-party talks that include the two Koreas, China, Japan, Russia and the United States "could reconvene this month."
