US President Barack Obama has reaffirmed his support for Japan in its row over islands with China, after talks with Prime Minister Shinzo Abe.
Mr Obama, who is on a four-nation Asia tour, warned against escalation in the dispute and said he wanted to see the row resolved peacefully.
But he confirmed that the islands fell under a security treaty that commits the US to act if Japan is attacked.
The two leaders also discussed a major trade deal as well as North Korea.
The US president arrived in Japan late on Wednesday ahead of stops in South Korea, Malaysia and the Philippines.
He is not going to Beijing but relations with China are expected to dominate his meetings with regional leaders.
Mr Obama’s trip – which ends on 29 April – comes nearly seven months after he cancelled a visit to the region because of a US government shutdown.
Officials say it is aimed at reassuring America’s Asian allies of its commitment to the region amid concern over China’s growing power.
On Wednesday Mr Obama had an informal dinner with Mr Abe. The two leaders then held talks on Thursday morning and gave a joint press conference.