TOKYO (Reuters) - The international community must remain united and enforce sanctions against North Korea after its repeated launch of ballistic missiles, Japanese Prime Minister Shinzo Abe said in an editorial published in the New York Times on Sunday. Abe s editorial was published before world leaders gather in New York for a United Nations General Assembly meeting this week, where North Korea s ballistic missile and nuclear weapons programmes are expected to loom large over proceedings. North Korea launched a missile over Japan on Friday, its second in the past three weeks, and conducted its sixth and by far most powerful nuclear test on Sept. 3, in defiance of international pressure. Such tests are in violation of U.N. Security Council resolutions and show that North Korea can now target the United States or Europe, Abe said. Diplomacy and dialogue will not work with North Korea and concerted pressure by the entire international community is essential to tackle the threats posed by North Korea, Abe wrote. A week ago, the 15-member U.N. Security Council unanimously adopted its ninth sanctions resolution since 2006 over North Korea s nuclear and ballistic missile programmes. 