US, Japan vow 'strong action' on N. Korea: Obama

Meeting Japanese Prime Minister Shinzo Abe, Obama said the two leaders spoke about "our concerns about the provocative actions that have been taken by North Korea and our determination to take strong actions in response."

Abe, who is known for his hard line on North Korea, said that he agreed with Obama on the need to press for a new UN Security Council resolution condemning Pyongyang.

"We just cannot tolerate the actions of North Korea such as launching missiles and conducting a nuclear test," said Abe, sitting next to Obama in the White House's Oval Office.

"We agreed that we would cooperate with each other in dealing resolutely with North Korea," he said.

Abe and Obama also spoke about Japan's rising tensions with China, although they took a measured tone in their public remarks.

The visit comes less than two weeks after North Korea carried out a third nuclear test in defiance of international sanctions backed by Pyongyang's close ally China, sending shockwaves across the region.

Earlier this week a US think tank said North Korea has resumed activity at the nuclear site following the internationally condemned test, raising fears the isolated, Stalinist-style regime could carry out more explosions.

Examining satellite photos, the US-Korea Institute at Johns Hopkins University detected a rise in traffic at the Punggye-ri site but cautioned that there was not enough evidence to assert that a new test was in the works.

Abe has moved to increase officially pacifist Japan's defense spending for the first time in more than a decade in a show of resolve toward Pyongyang and Beijing.

Ahead of his visit, Abe told The Washington Post that China's stance of "coercion and intimidation" would eventually hurt its investment climate, triggering a rebuke from Beijing.