Image copyright Reuters Image caption Japan's Prime Minister Shinzo Abe played a round of golf with US President Donald Trump

US President Donald Trump has dismissed concerns about recent North Korean missile tests, appearing to contradict his own national security adviser.

In a tweet issued shortly after his arrival in Japan on Sunday, Mr Trump called the missiles "small weapons".

US National Security Adviser John Bolton said on Saturday that the tests violated UN resolutions on North Korea.

President Trump began a state visit to Japan on Sunday by teeing off a round of golf with Prime Minister Shinzo Abe.

The two leaders ate breakfast together on Sunday, before heading out to play 16 holes of golf in Chiba, outside the capital Tokyo.

Mr Trump has said he wants to strike a deal with Japan to address what he has called a trade imbalance between the two countries.

Mr Trump wrote: "North Korea fired off some small weapons, which disturbed some of my people, and others, but not me." He added: "I have confidence that Chairman Kim will keep his promise to me."

Not for the first time, his tweet appeared to put him at odds with Mr Bolton, and also with his host nation. Mr Abe last week called the North Korean tests "extremely regrettable".

Mr Bolton and Mr Abe both accused North Korea of violating UN resolutions.

The contrast between the president and his national security adviser followed other recent divergences on foreign policy, including how to approach the crisis in Venezuela and US relations with Iran.

What weapons has North Korea recently tested?

A rapprochement between North Korea and the US appeared to be in the offing last year after Mr Trump and Mr Kim met in Singapore.

But relations have soured in recent months after a second summit between the leaders in Vietnam ended without agreement.

Amid the rising tensions, North Korea has carried out several weapons tests.

Image copyright Reuters Image caption The second summit between President Trump and Mr Kim ended without agreement

Earlier this month, the regime tested several short-range missiles, launching them from the Hodo peninsula in the east of the country. North Korean state media said Mr Kim personally oversaw a "strike drill" testing various missile components.

That test came after Pyongyang said it had tested what it described as a new "tactical guided weapon" in April.

Neither violate North Korea's promise not to test long range or nuclear missiles. Yet, they are likely to cause unease in Japan.

Speaking in Tokyo last week, Mr Abe mirrored Mr Bolton's comments, calling North Korea's recent missile launches "a breach of UN Security Council resolutions and extremely regrettable".

"While cooperating closely with the US and other related countries, we are planning to tackle this appropriately by strengthening enforcement of related UN Security Council resolutions," he said.

North Korea fired a number of missiles over Japan in 2017, leading Mr Trump to tell Mr Abe his country could intercept missiles "if necessary".

Image copyright Reuters Image caption Kim Jong-un held talks with the US president in February

Why is Trump in Japan?

The US president is there to discuss trade and security issues. North Korea's missile tests and nuclear programme are expected to be at the top of the agenda.

Japan is considered to be one of America's most important allies, for security and economic reasons, and Mr Trump has sought to strengthen the relationship, making regular diplomatic trips to meet Mr Abe.

Their shared love of golf is one way they have bonded. They teed off on Sunday for a round at the Mobara course in Chiba.

Aside from golf, Mr Trump will attend the final day of the sumo "basho" or tournament and meet Japan's new emperor, Naruhito.

He will be the first foreign leader to meet the new emperor, who ascended the Chrysanthemum Throne at the beginning of the month.

Meanwhile, trade talks involving Trump's top trade representative Robert Lighthizer and his Japanese counterpart, Economy Minister Toshimitsu Motegi, are taking place.

They are aiming to make progress on negotiating a trade deal between the two countries.

Mr Trump believes their trading relationship is unfair. He told business leaders in Tokyo on Saturday that "Japan has had a substantial edge for many, many years".

The trade situation will become "a little bit more fair", Mr Trump said, without elaborating.