North Korea denounced the US deployment of a naval strike group to the region on Tuesday, warning it is ready for “war” as Washington tightens the screws on the nuclear-armed state.

The strike group—which includes the Nimitz-class aircraft supercarrier USS Carl Vinson—cancelled a planned trip to Australia this weekend, heading to the Korean peninsula instead in a show of force. “This goes to prove that the US reckless moves for invading the DPRK have reached a serious phase,” a spokesman for the North’s foreign ministry said according to state news agency KCNA.

“The DPRK is ready to react to any mode of war desired by the US,” he said, using the country’s official name, the Democratic People’s Republic of Korea.

President Donald Trump, fresh from ordering a missile strike on Syria that was widely interpreted as a warning to North Korea, has asked his advisors for a range of options to rein in Pyongyang, a top US official said on Sunday.

But Pyongyang’s response suggested the reclusive state is determined to continue on its current path, despite repeated rounds of United Nations sanctions. “We will take the toughest counteraction against the provocateurs in order to defend ourselves by powerful force of arms,” the foreign ministry spokesman said. “We will hold the US wholly accountable for the catastrophic consequences to be entailed by its outrageous actions.”

Speculation over an imminent nuclear test is brewing as the North marks anniversaries including the 105th birthday of its late founder on Saturday—sometimes celebrated with a demonstration of military might.

Thousands of troops and top military officials gathered in Pyongyang on Monday to pledge loyalty to leader Kim Jong-Un ahead of his grandfather’s birth anniversary, state media said.

State TV showed thousands of goose-stepping soldiers marching in unison, carrying giant portraits of the regime’s founder Kim Il-Sung and his son, Kim Jong-Il, in front of the Kumsusan mausoleum where their embalmed bodies are on display.

“If they (the US and the South) try to ignite the spark of war, we will wipe out all of the invaders without a trace with... our strong pre-emptive nuclear strike,” Hwang Pyong-So, director of the political bureau at the North’s army, said in a speech.

The South’s PM and acting president warned of a “grave provocation” by the North to coincide with other anniversaries, including the army’s founding day on April 25.

“There is a possibility that the North launches more grave provocations such as another nuclear test to mark a number of anniversaries,” Hwang Kyo-Ahn said in a cabinet meeting.

‘US ready to solve problem sans China’

US President Donald Trump said  on Tuesday that the United States is ready to solve the North Korean “problem” without China if necessary.

“North Korea is looking for trouble,” Trump wrote on Twitter. “If China decides to help, that would be great. If not, we will solve the problem without them! U.S.A.”

Trump launched a missile strike on Syria late Thursday while meeting with Chinese leader Xi Jinping at his Mar-a-Lago resort in Florida.

The move was widely interpreted as a warning to North Korea as well as retaliation for the Damascus regime’s suspected sarin attack against civilians in a rebel-held town in Syria.

“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!” Trump wrote in an earlier tweet.