SEOUL-- South Korea is keeping close tabs on North Korea in close consultation with the United States amid recent signs of the secretive nation repairing its nuclear testing site, the unification ministry said Monday.
The ministry urged Pyongyang to immediately cease all relevant activities and return to the negotiating table.
Informed sources here said earlier the North seems to be seeking to make a "shortcut" to a tunnel at its once-defunct nuclear testing site in Punggye-ri.
The move is seen as aimed at making speedy preparations for a seventh underground nuclear experiment.
Speaking at a press briefing, Lee Jong-joo, the ministry's spokesperson, pointed out that North Korea's next move is unpredictable.
"But our government is taking thorough measures to prepare for all possibilities in close consultation with the United States," she added.
Source: Yonhap News Agency