President Donald Trump on Tuesday morning said “all options” remain in play after North Korea fired a missile over Japan’s northern island on Monday.

“The world has received North Korea’s latest message loud and clear: this regime has signaled its contempt for its neighbors, for all members of the United Nations, and for minimum standards of acceptable international behavior,” Trump said in a statement issued more than 12 hours after the launch.

“Threatening and destabilizing actions only increase the North Korean regime’s isolation in the region and among all nations of the world,” Trump said. “All options are on the table.”

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Air raid sirens sounded in Japan, but the government there decided against trying to shoot down the missile.

Trump spoke Monday with Japanese Prime Minister Shinzo Abe after the launch, the White House said. The pair “agreed that North Korea poses a grave and growing direct threat to the United States, Japan, and the Republic of Korea, as well as to countries around the world.” 

Trump and Abe are “committed to increasing pressure” on Pyongyang, the statement said, but it did not explain how Trump and Abe intend to do that.

Trump continued to leave open the possibility that U.S. military force might be needed to weaken or take down North Korea’s nuclear and missile arsenals. His Tuesday statement left that option on the table, but it was less hawkish than some of his previous statements.

On Aug. 9, he tweeted an implicit warning to North Korea Wednesday morning, tweeting the U.S. nuclear arsenal is “far stronger and more powerful” than it ever has been.

And last Tuesday night at a raucous campaign rally in Phoenix, Trump sent mixed signals. He both rattled his sabre and seemed to express interest in a peaceful outcome.

“And you see what’s going on in North Korea. All of a sudden, I don’t know — who knows. But I can tell you, what I said, that’s not strong enough,” Trump said, referring to his pledge to order “fire and fury” on the isolated nation if it doesn’t change its behavior.

“Some people said it’s too strong,” he added. “It’s not strong enough.”

“But Kim Jong Un, I respect the fact that I believe he is starting to respect us. I respect that fact very much. Respect that fact,” the commander-in-chief said. “And maybe — probably not — but maybe something positive can come about.”