Illinois governor seeks assurances from Joint Chiefs of Staff after Signal incident

Gov. JB Pritzker said he's "lost faith" in Secretary of Defense Pete Hegseth.

Illinois Gov. JB Pritzker asked the Joint Chiefs of Staff to give assurances to all of the states and their governors about the specific steps being taken to protect national security in the wake of the recent use of the Signal messaging app by members of President Donald Trump's administration to discuss sensitive foreign policy plans.

The Democratic governor sent a letter on Monday to acting Chairman of the Joint Chiefs of Staff Christopher Grady – obtained exclusively by ABC News – asking that he intervene on behalf of service members' safety.

Pritzker said he was reaching out as he's "lost faith" in the ability of Secretary of Defense Pete Hegseth, one of the key members of the Signal incident, to "maintain the integrity of our national defense operations."

"I am reaching out to you as our nation's highest-ranking military officer as I have lost faith in the ability of the Secretary of Defense to keep service members safe and maintain the integrity of our national defense operations," Pritzker wrote in the letter.

The governor's office did not comment on the letter in response to a request from ABC News.

"Please detail the exact steps the federal government will take to reign in dangerous and egregious behavior that compromises national security, and the steps it will take to ensure that appropriate, safe channels, methods, and protocols are used to protect classified information and secure communications," Pritzker also requested.

He said he's seeking this information while keeping in mind the nearly 13,000 military personnel serving in the Illinois National Guard.

"The Secretary's carelessness not only put the lives of the pilots executing the operation at risk, but it put the lives of troops around the world on the line – including service members from the Illinois National Guard," Pritzker wrote.

"Currently, over 1,700 Illinois National Guard members are deployed on federal active-duty service by directive of the President, so I cannot not stand by silent as their lives are put at risk," he added.

Pritzker, who has been on the forefront of pushing back against Trump and his policies among Democrats nationwide, recently returned from a four-day trip to Mexico that was meant to boost economic partnerships between it and Illinois.

ABC News has reached out to Grady's office for a response to Pritzker's letter.