The nation’s top military officer said Tuesday he’s not seen any shifts in North Korea’s military posture despite the reclusive nation’s threats to shoot down U.S. warplanes amid the “charged political environment” between Washington and Pyongyang.

Marine Corps Gen. Joseph Dunford, chairman of the Joint Chiefs of Staff, told the Senate Armed Services Committee “we haven’t seen military activity that would be reflective of the charged political environment that we’re seeing.”

His remarks come amid escalating rhetoric between President Donald Trump and North Korean leader Kim Jong Un. Trump tweeted that North Korea’s leadership “won’t be around much longer.” North Korea’s top diplomat, Ri Yong Ho, argued Trump’s tweet gives his nation the right to shoot down U.S. military aircraft, like the strategic bombers Washington flew close to the border between the two Koreas over the weekend.

The White House said Monday it’s not seeking to overthrow North Korea’s government and called Pyongyang’s assertion absurd that Trump’s comment amounted to a declaration of war.

Still, the fiery rhetoric carrying over from a week of threatening exchanges at the U.N. General Assembly only further stoked concerns the U.S. and North Korea would lurch into an open military conflict. The Korean War ended seven decades ago without a formal peace treaty and tensions related to the North’s nuclear advances have escalated for months.

Dunford also indicated that reaching a diplomatic solution with North Korea may be more difficult if the U.S. abandons the landmark nuclear deal with Iran. Trump has suggested he might seek to renegotiate or walk away from what he’s labeled the “worst one-sided deal perhaps in American history.”

But Dunford cautioned that ditching the deal could have ramifications.

“It makes sense to me that our holding up agreements that we have signed, unless there’s a material breach, would have an impact on others’ willingness to sign agreements,” Dunford said.

The general said that Iran is adhering to its obligations under the nuclear agreement.

Dunford completes his first term at the end of September. The committee was holding his confirmation hearing with just days to spare to give him another tour of duty. The full Senate must vote to confirm Dunford by Saturday or he’ll have to step aside until his nomination is approved.

Trump in May nominated Dunford to serve a second two-year term as chairman as most military leaders serve two terms. President Barack Obama had tapped Dunford for the job.

During the wide-ranging hearing, Dunford voiced support for currently serving transgender troops, telling the panel that anyone who meets the military’s demanding standards and is capable of deploying should be allowed to continue to serve. Trump directed the military to indefinitely extend the ban on transgender individuals enlisting in the service, but he left it up to Defense Secretary Jim Mattis to decide if those currently serving should be allowed to stay.

Sen. Kirsten Gillibrand, D-N.Y., asked Dunford if he would promise that transgender troops who have followed department policy and met every requirement would not be dismissed from the armed forces based solely on their gender identity.

“I can promise that that will be my advice,” Dunford responded. “What I’ve just articulated is the advice I’ve provided in private, and I’ve just provided in public.”

In a recent memo to top military leaders, Mattis said a high-level panel will determine how to implement Trump’s ban on transgender individuals in the military. The guidance also made clear that transgender troops in uniform can re-enlist in the next several months, even as the department debates how broadly to enforce the ban Trump ordered.

Dunford, a highly respected, combat-hardened commander, took over as chairman on Oct. 1, 2015, following just one year as commandant of the Marine Corps. Before that assignment, he led the Afghanistan war coalition during a key transitional period from February 2013 to August 2014.

During his fast-tracked military career that began in 1977, Dunford jumped from a one-star general to four stars in about three years. He’s steadfastly steered clear of politics and urged all U.S. troops to do the same.

Dunford, 61, is a Boston native who holds master’s degrees in government from Georgetown University and international relations from Tufts University’s Fletcher School of Law and Diplomacy.