(Recasts with U.S., Japan moving to increase sanctions)
TAORMINA, Italy, May 26 (Reuters) - U.S. President Donald Trump and Japanese Prime Minister Shinzo Abe agreed on Friday to expand sanctions against North Korea for its continued development of nuclear weapons and ballistic missiles, the White House said.
Pyongyang has carried out repeated missile tests in the past year, prompting an array of countries to demand tougher economic sanctions to push the isolated country towards dismantling its weapons programmes.
Meeting before a Group of Seven summit, Trump and Abe dedicated most of their discussions to the issue, aides said.
"President Trump and Prime Minister Abe agreed their teams would cooperate to enhance sanctions on North Korea, including by identifying and sanctioning entities that support North Korea's ballistic missile and nuclear programs," the White House said in a statement.
"They also agreed to further strengthen the alliance between the United States and Japan, to further each country's capability to deter and defend against threats from North Korea," it said.
Trump has said he will prevent North Korea from being able to hit the United States with a nuclear missile, a capability experts say Pyongyang could have some time after 2020.
"It is very much on our minds...It's a big problem, it's a world problem and it will be solved. At some point it will be solved. You can bet on that," Trump told reporters, sitting alongside Abe.
U.S. Secretary of State Rex Tillerson this month called on countries all over the world to implement existing U.N. sanctions on North Korea's nuclear weapons and missile programs, adding that the U.S. administration would be willing to use secondary sanctions to target foreign companies that continue to do business with Pyongyang. of North Korea's trade is with its ally China, and so any hard-hitting secondary sanctions would likely target Chinese firms.
Speaking in Beijing, a senior U.S. State Department official said on Friday that China realised it has limited time to rein in North Korea through negotiations and that it was open to further sanctions. Thornton, the acting assistant secretary for East Asian and Pacific affairs told reporters the United States was looking at discussing with China a new U.N. Security Council resolution on measures to reduce delays in any response to further nuclear tests or other provocations from the North.