South Korea's president said Leaders of five nations will discuss ways to press North Korea to scrap a planned rocket launch when they meet next week at a Seoul summit.
US President Barack Obama will attend the nuclear security summit, along with leaders of China, South Korea, Japan and Russia. All the countries have been involved since 2003 in talks to shut down the North's nuclear programme.
The nuclear-armed North has announced it will launch a rocket next month to put a satellite into orbit, a move which the US and its allies see as a pretext for a long-range missile test.
A UN Security Council resolution passed after the North's missile and nuclear tests in 2009 bans a ballistic missile launch for any purpose.