NKorea missile tests 'provocative': Obama

US President Barack Obama has called on other nations to implement sanctions fully against North Korea after a series of missile tests.

US President Barack Obama has called for the full implementation of sanctions against North Korea after it fired three ballistic missiles towards the Sea of Japan.

Obama noted that the firing of the missiles, which occurred while leaders of the Group of 20 major economies were meeting in China, highlighted the threat posed by Pyongyang.

"These launches are provocative," he told reporters after meeting with South Korean President Park Geun Hye on the sidelines of a South-East Asian summit in Laos.

He called on other nations to "implement sanctions fully" against Pyongyang.

Park called the tests "fundamentally threatening" and stressed the need to close "loop holes in sanctions" against North Korea in response to its missile tests.

Tensions have been higher on the Korean peninsula following a series of tests by North Korea at the start of the year, including an atomic test.