Japan and China agreed to oppose a nuclear North Korea on Wednesday and to continue seeking a solution within six-party disarmament talks, a report said.
Japanese vice foreign minister Mitoji Yabunaka was visiting Beijing to meet his Chinese counterpart Wang Guangya.
China is North Korea's main ally and has always favoured cautious diplomacy with Pyongyang.
"Basically, there was a complete agreement that we could definitely not allow possession of nuclear arms by North Korea," Yabunaka told reporters in Beijing.
"Both sides will adhere to the UN Security Council resolution and will pursue denuclearisation in a persistent manner," he said, quoted by Kyodo News.
Tensions on the Korean peninsula have been running high since Pyongyang carried out its second nuclear test last month.
After the underground test and subsequent missile launches, the Security Council adopted a resolution that includes financial sanctions designed to choke off revenue to the regime.
North Korea has already vowed to build more bombs and to start a new weapons programme based on uranium enrichment in response to the sanctions.
The meeting was part of a high-level strategic dialogue held regularly between Japan and China.