The President made the remark after he had a telephonic conversation with his Chinese counterpart Xi Jinping.

"Certainly that's not a first choice, but we'll see what happens," CNN quoted Trump as saying on military action against North Korea.

Meanwhile, an official statement issued by the White House said both the leaders discussed the Sept 3  test of a powerful nuclear device that was carried out by North Korea.

"President Donald J. Trump spoke today with President Xi Jinping of China to discuss North Korea’s September 3 test of a powerful nuclear device.  The two leaders condemned North Korea’s latest provocative and destabilizing action and noted North Korea’s current path is dangerous to the world and not in its own interest," the White House said in a statement.

"President Trump and President Xi committed to strengthen coordination and take further action with the goal of achieving the denuclearization of the Korean Peninsula," it said.

President Donald Trump on Tuesday said his government is selling Japan and South Korea a “substantially increased” amount of US military equipment.

The President made the announcement amid heightened tension in the Korean peninsula.

"I am allowing Japan & South Korea to buy a substantially increased amount of highly sophisticated military equipment from the United States," Trump said.

North Korean state-run media on Sunday reported that the country has successfully tested a Hydrogen Bomb, which is way more powerful than an atomic bomb.

This was the reclusive nations's sixth test, according to reports.

According to South Korean media reports, the latest test was conducted near Kilju County, where the North's Punggye-ri nuclear test site is situated.

The tremor felt was 9.8 times more powerful than the one from the fifth test, the country's state weather agency said.

South Korean President Moon Jae-in urged the world for the "strongest" response to the test and further isolate North Korea, including imposing new UN Security Council sanctions, according to Yonhap state news agency.

According to a CNN report, Chung Eui-yong, the South Korean President’s chief security advisor, said that South Korea will seek diplomatic measures to “completely isolate” North Korea.

“North Korea today ignored the repeated warnings from us and the international society and conducted a stronger nuclear test than before,” he told reporters, reported the US media.

“President Moon has ordered the most powerful response to condemn [North Korea], along with the international society and decided to seek diplomatic measures such as pushing ahead for an UNSC resolution to completely isolate North Korea,” it said.

Earlier, the Kim Jong-un led government had claimed that they have successfully managed to miniaturise a nuclear weapon that can be loaded on to a missile.

The development looks ominous as the reclusive nation has already threatened the US.

Even though many, including the American President Donald Trump, speculates the gravity of the threat, US intelligence have told the Washington Post that North Korea has progressed at a much faster rate than expected and is capable of striking the US.     

In the past, Kim and his men have conducted umpteen tests, ignoring sanctions against them, but have mostly failed to threaten the likes of the US, against whom it plans to mount an attack.

However, the repeated tests have kept countries like Japan, South Korea, China and Russia on alert.

Recently, the Pyongyang confirmed that it flew a projectile over Japanese air-space.

The missile was 'personally guided' by Kim.

Even though it physically didn't damage anything, except the already battered bi-lateral ties, the move was met with much scorn by the Japanese Prime Minister Shinzo Abe.

North Korea's antics also halted several operations in Japan as residents were ordered to stay indoor and take cover.

A day later, Kim Jong-un was quoted in the state-run media as saying that the launch was a "meaningful prelude to  containing" the US Pacific territory of Guam.

The North Korean leader also warned of further strikes.

Experts believe that the strikes are in connection with the latest sanction it faces from the United Nations, where the US played a major role.

According to the new sanctions, importing coal, seafood, iron and iron ore, lead and lead ore from North Korea is banned.

Under the new rule, no country can hire or receive North Korean workers.

Countries have also been barred from entering into ventures from North Korea.

The member states will have to report within 90 days on how they have gone about the job.