Hersh wrote on Substack earlier this month, based on a single anonymous source, that the U.S. was involved in the sabotage of the pipelines.

Asked by Bream whether the administration would have an obligation to inform Congress of such an operation, Kirby said: “Obviously, we keep Congress informed appropriately of things both classified and unclassified. But I can tell you now, regardless of the notification process, there was no U.S. involvement in this.”

Hersh is a Pulitzer-winning journalist best known for his expose of the 1968 My Lai Massacre committed by U.S. troops in Vietnam and the Pentagon’s efforts to cover it up. In 2004, he chronicled the military’s torture of prisoners at Abu Ghraib in Iraq. But he has also drawn criticism for some of his reporting in recent years, including his challenges to the official U.S. account of the killing of Osama bin Laden in Pakistan.

Russia, which invaded Ukraine a year ago this week, has relied on its income from energy exports to fund the war. President Joe Biden sanctioned the Russian company behind the pipelines last year.

David Cohen contributed to this report.