■Rep. Mike Turner urges Biden administration to declassify national security threat.

■Threat may relate to a space-deployed Russian anti-satellite weapon.

■Lawmakers and White House assure public there’s no need for alarm.

WASHINGTON — The Republican head of the House Intelligence Committee urged the Biden administration on Wednesday to declassify information about what he called a serious national security threat.

Rep. Mike Turner gave no details about the nature of the threat, and the Biden administration also declined to address it. But several leading lawmakers, including House Speaker Mike Johnson, cautioned against being overly alarmed.

A senior congressional aide said he understood that the threat relates to a space-deployed Russian anti-satellite weapon that may or may not already have been deployed. Such a weapon could pose a major danger to U.S. satellites that transmit billions of bytes of data on an hourly basis.

The aide, speaking on condition of anonymity due to the sensitivity of the matter, said it was not yet clear if the Russian weapon has nuclear capability, but said that is the fear.

Urgent Matter Identified

Turner earlier Wednesday sent an email to members of Congress saying his committee had “identified an urgent matter with regard to a destabilizing foreign military capability” that should be known to all congressional policy makers. He encouraged them to come to a SCIF, a secure area, to review the intelligence.

Turner has been a voice for stronger U.S. national security, putting him at odds with some Republican colleagues who favor a more isolationist approach. He has called for the renewal of a key U.S. government surveillance tool while some fellow Republicans and liberal Democrats have raised privacy objections.

And he supports continuing U.S. military aid for Ukraine in its war against Russia at a time that the funding remains uncertain because of opposition in the Republican-led House.

Reactions to the Threat

Johnson said he was not at liberty to disclose the classified information. “But we just want to assure everyone steady hands are at the wheel. We’re working on it and there’s no need for alarm,” he told reporters at the Capitol.

Democratic Rep. Jim Himes, the ranking member of the Intelligence Committee, said in a statement that the classified information is “significant” but “not a cause for panic.”

The Senate Intelligence Committee said it has been tracking the issue.

“We continue to take this matter seriously and are discussing an appropriate response with the administration,” Sen. Mark Warner, the Democratic committee chairman, and Sen. Marco Rubio, the Republican vice chairman, said in a statement. “In the meantime, we must be cautious about potentially disclosing sources and methods that may be key to preserving a range of options for U.S. action.”

The White House and lawmakers expressed frustration at how Turner raised his concerns. His announcement appeared to catch the Biden administration off-guard.

National security adviser Jake Sullivan told reporters at the White House that he already had been due to brief Turner and other senior congressional leaders on Thursday. Sullivan did not disclose the topic or provide any other details related to Turner’s statement.

“I’m focused on going to see him, sit with him as well as the other House members of the Gang of Eight, tomorrow,” Sullivan said. “And I’m not in a position to say anything further from this podium at this time.”

He acknowledged it was not standard practice to offer such a briefing.

“I’ll just say that I personally reached out to the Gang of Eight. It is highly unusual, in fact, for the national security adviser to do that,” Sullivan said. He said he had reached out earlier this week.

Johnson said he sent a letter last month to the White House requesting a meeting with the president to discuss “the serious national security issue that is classified.” He said Sullivan’s meeting was in response to his request.