North Korea's firing of a barrage of projectiles into the East Sea underscores the importance of the new U.N. resolution imposing new sanctions on Pyongyang and its stringent implementation, the State Department said Thursday.

The North fired six short-range projectiles off its east coast Thursday in an apparent gesture of defiance just hours after the U.N. Security Council unanimously adopted the harshest-ever sanctions on Pyongyang for carrying out its fourth nuclear test on Jan. 6 and its long-range rocket launch on Feb. 7.

The launches, believed to be involving 300 mm rockets or short-range missiles, could be a message to the outside world that the communist nation remains unfazed by the new sanctions and will forge ahead with its nuclear and missile programs.

"Not exactly surprising. It's typical of the kind of response that we have seen from them in the past. Is it provocative?

Absolutely, it is. There's no doubt about that," State Department spokesman John Kirby said of the launches at a regular press briefing.

"If true that they fired off these missiles, it would just be another example of increasingly provocative, unnecessarily provocative conduct by Pyongyang," he said. "That only underscores the importance of the resolution that was passed yesterday and the resolve of the international community in a unified way to enact more robust measures."

Kirby also said the U.S. is currently focused on ensuring robust implementation of the new U.N. sanctions.

The U.N. Security Council adopted Resolution 2270, significantly tightening the screws on the communist nation that sparked global outrage with its fourth nuclear test on Jan. 6 and its long-range missile launch on Feb. 7 in violation of U.N. bans.

The new sanctions, the toughest ever to be imposed on Pyongyang, require mandatory inspection of all cargo going in and out of the North, regardless of whether by land, sea or air, while banning its exports of coal, iron and other mineral resources, a key source of hard currency that accounts for nearly half of the country's total exports. (Yonhap)