South Korea has insisted it will go ahead with a controversial live-fire military exercise, despite serious concern expressed by Russia and China, BBC News reported. A defence ministry official said the exercise, in a disputed area, would go ahead once bad weather had lifted. North Korea says the drill, on the island it shelled last month with four lives lost, would be a provocation and has threatened to retaliate. An emergency session of the UN Security Council was to meet later on Sunday.