South Korea requested the U.N. Security Council hold an emergency meeting at 11:00 p.m. (Seoul time) as North Korea is believed to have conducted a nuclear test, a Seoul diplomat said Tuesday.

The U.N. Security Council meeting will be held at 9:00 a.m. (New York time) on Tuesday, according to the diplomat.

South Korea is trying to verify whether North Korea has conducted a nuclear test after detecting an "artificial earthquake"

near the North's nuclear test site earlier in the day.

A senior official at Seoul's foreign ministry said the government saw a "high possibility" that North Korea may have conducted an atomic test. (Yonhap News)