The Biden administration reached “side understandings” to allow Israel to continue bombing targets in Lebanon despite a ceasefire reached late last year, according to Michael Herzog, who was then serving as Israel’s ambassador to the U.S.

Herzog revealed the handshake deal, which had not previously been confirmed, during a Friday panel at the Washington Institute for Near East Policy. One key result of the agreement, which Herzog helped negotiate, was maintaining Israel’s “freedom of action against threats” when other parties are “unwilling or incapable” of containing them, he said. “That was achieved through side understandings with the government of the United States,” Herzog said. “And it’s been implemented in Lebanon.”

The revelation helps explain why the U.S. has stayed relatively quiet over the last year about alleged Israeli ceasefire violations, including near daily airstrikes and commando raids against what Israel claims are Hezbollah-related sites in southern Lebanon. These attacks, which have killed at least 100 Lebanese civilians, seem to represent a far cry from the “permanent cessation of hostilities” that President Joe Biden claimed would follow the ceasefire.

Rumors of such a deal have circulated over the past year following Israeli mediareports about the existence of a “side letter” allowing Israel to “defend itself” against threats in Lebanon provided that Israeli forces notify the U.S. in advance. But Herzog’s comments appear to represent the first official confirmation of the secret agreement — and the clearest indication yet that Israel views the side deal as giving it carte blanche to continue its unilateral air campaign against Hezbollah.

Herzog did not explicitly say whether these “side understandings” remain in place under the Trump administration, which, like the Biden administration, has largely ignored alleged Israeli violations of the ceasefire.

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