The military and the National Intelligence Service have been meeting regularly since early March to assess information about North Korea, a military source said Wednesday.

The two sides apparently agreed to share information after criticism that by working in isolation they failed to avert the North's attacks on the Navy corvette Cheonan and Yeonpyeong Island last year.

In the past, they were chary of their insights and met only very occasionally to share intelligence if they felt it warranted scrutiny.

A researcher at a government-funded security think tank said, "Intelligence agencies tend to monopolize high-level intelligence. Even if they meet every day, it may still be difficult for the military and the NIS to assess information accurately, so it's a surprise they didn't regularly share military intelligence about the North until recently."

A Defense Ministry official denied lack of intelligence sharing was to blame. "In cooperation with intelligence agencies like the NIS, the ministry has been assessing possible signs of the North launching provocations since the sinking of the Cheonan," he claimed. "The allegation that the military and the NIS are handling military intelligence about the North separately is not true."

But neither side issued any warning of the possibility of an attack from the North even when they detected unusual movements in the North ahead of the shelling of Yeonpyeong Island in November last year.