 -- After wrapping up a meeting with Chinese President Xi Jinping last week, President Trump charged today that North Korea is "looking for trouble" and if China isn't willing to help tamp down the threat, the U.S. "will solve the problem" alone.

"I explained to the President of China that a trade deal with the U.S. will be far better for them if they solve the North Korean problem!" President Trump tweeted of his two-day summit with Xi at his Mar-a-Lago resort.

"North Korea is looking for trouble. If China decides to help, that would be great," Trump wrote. "If not, we will solve the problem without them!"

North Korea launched a ballistic missile in the Sea of Japan last Tuesday - its fourth missile test so far this year. U.S. officials have also speculated that the hermetic nation could launch another missile test on April 15, the birthday of North Korea's founder Kim il Sung.

Over the weekend, the USS Carl Vinson aircraft carrier was ordered to head to the Sea of Japan. North Korea reacted strongly today against the carrier's deployment. “We will hold the US wholly accountable for the catastrophic consequences to be entailed by its outrageous actions,” a foreign ministry spokesman said, according to The Associated Press.

The AP reported that a North Korean official said the U.S. airstrikes in Syria prove its nuclear program is necessary to protect itself against "evermore reckless moves for a war" from the U.S.

In an interview with ABC News' "This Week" on Sunday, Secretary of State Rex Tillerson was asked what message the U.S. is sending to North Korea.

"I think the message that any nation can take is if you violate international norms, if you violate international agreements, if you fail to live up to commitments, if you become a threat to others, at some point a response is likely to be undertaken," Tillerson responded.

"The two sides noted the urgency of the threat of North Korea's weapons programs, reaffirmed their commitment to a denuclearized Korean peninsula, and committed to fully implement UN Security Council resolutions," the White House said in a statement Friday night following President Xi's visit. "They agreed to increase cooperation and work with the international community to convince North Korea to peacefully resolve the issue and dismantle its illegal nuclear and missile programs."

The White House did not offer more specifics on how the two countries will approach the growing threat from North Korea's nuclear program.

When asked about whether Trump convinced President Xi to take a more aggressive approach to North Korea, Tillerson would not elaborate much more than saying the two leaders agree that the North Korea situation has "reached a new level of seriousness and threat."

"[President Xi] expressed a view that he wanted to be supportive in terms of causing the regime in Pyongyang to change its view around the future need for those weapons," Tillerson said on "This Week."

Tillerson also said the U.S. has "called on the government of China to take additional steps."

"I think we need to allow them time to take actions and we will continue to be in very close discussions with them," Tillerson said, adding that the conversations between the two countries have been "very candid."

Trump's two Twitter posts echoed what he told the Financial Times earlier this month.

“Well, if China is not going to solve North Korea, we will. That is all I am telling you," Trump told the FT.

ABC News' Elizabeth McLaughlin and Katherine Faulders contributed to this report.