The threat of North Korea was at the forefront of discussions between Donald Trump and his Asian allies as they sought a solution to the "menace" posed by the volatile nation.
North Korea's test launch of an intercontinental ballistics missile (ICBM) earlier this week ensured the issue of Kim Jong-un's escalating aggression was an area of great concern among G20 leaders.
The U.S. President told his Chinese counterpart Xi Jinping: "Something's got to be done about it" when their pair met at the G20 summit.
In a separate meeting with Japanese Prime Minister Shinzo Abe, Mr Trump said the two were tackling "the problem and menace of North Korea."
As President Trump wrapped up his second European tour at the G20 summit, the White House said the U.S. was "prepared to use the full range of capabilities" to defend Japan.
Presidents Trump and Abe were committed "to redoubling their efforts to bring all nations together to show North Korea that there are consequences for its threatening and unlawful actions", the White House added.
Until very recently, the Trump administration had pressured Beijing to rein in North Korea - a major trading partner - in a bid to halt Kim Jong-un's development of nuclear weapons before they have the ability to threaten the U.S. homeland.
Trump has been critical of China in recent days, claiming North Korea's neighbour hasn't done enough.
However, during his meeting, Trump told Xi: "I appreciate the things that you have done relative to the very substantial problem that we all face in North Korea."
Trump's extensive slate of meetings with Abe, Xi, British Prime Minister Theresa May and others came on the final day of the annual Group of 20 summit, which has been marked by violent demonstrations by anti-globalisation activists.
Trump also had a brief, unscheduled meeting with Turkey's President Recep Tayyip Erdogan about the situation in Syria.
Speaking through a translator, Abe noted that the security situation in the Asia Pacific region has become "increasingly severe" due to North Korea's push to develop its ballistic missile and nuclear program.
Abe said he wanted to "demonstrate the robust partnership as well as the bonds" between Japan and the U.S. on the issue.
North Korea's successful test launch of an ICBM was a major milestone in its long-term effort to build a missile that could carry a nuclear warhead to attack the United States.
The issue was a frequent topic of discussion at the summit, and the White House said earlier that the U.S., South Korea and Japan were pressing for additional measures against North Korea to demonstrate the "serious consequences" for its latest provocations.
The three nations have been calling for "early adoption" of a new U.N. Security Council resolution and additional sanctions to demonstrate to Pyongyang the consequences of its actions.
Bringing China on board is a key part of the plan. The administration wants China to fully enforce international sanctions intended to starve Pyongyang of revenue for its nuclear and missile programs. But Trump has been dissatisfied with China's response.
Trump planned to return to Washington on Saturday evening after the conclusion of the annual G-20 meetings. He won't be stateside for long: The president is scheduled to return to Europe next week to attend Bastille Day celebrations in Paris.