(FOX 5 NEWS) - President Donald Trump's national security team held a rare briefing open to all 100 U.S. senators on the tensions with North Korea. Senators arrived by the bus load and filed into the Eisenhower Executive Office Building for the classified briefing. Trump's top national security advisors told lawmakers North Korea poses a very grave threat.
"The president has made clear that a North Korea that is armed with a nuclear-armed missile, a capability they have yet to test, is unacceptable to us," Senate Majority Leader Mitch McConnell said.
Some Democrats criticized the location of the White House meeting because similar briefings are usually held at the Capitol. Some suggested the president's plan to "drop by" the meeting was just a clever photo op ahead of his one 100th day in office.
Sen. Ted Cruz, R-Texas, spoke to reporters after the Senate briefing.
"North Korea is the most dangerous spot on the planet right now," Cruz said. "And Kim Jong-Un is a dangerous and wildly unpredictable dictator, who unfortunately has a significant arsenal of nuclear weapons."
Trump wants to increase diplomatic pressure on North Korea with economic sanctions. The goal is to get North Korea to dismantle its nuclear weapons.
In South Korea, U.S. and South Korean troops are doing a series of joint exercises in the event of a possible invasion from North Korea. The air force test-fired an intercontinental ballistic missile.
"The U.S. Army and both air forces have a variety of capabilities that are ready to fight tonight, if necessary," Army Col. Matthew Garner said.
A North Korean Foreign Ministry spokesman denounced the Trump administration's aggressive posture, saying that if war breaks out on the Korean peninsula, "the U.S. will be held wholly accountable."
After the classified briefing with senators at the White House, the president's top security advisors held another one for House members back on Capitol Hill.
While lawmakers seemed to agree that North Korea is a real threat, the Trump administration did not talk to lawmakers about a preemptive strike on North Korea, according to Rep. Eliot Engel of New York, a member of the House Foreign Affairs Committee.