The classified information that President Donald Trump shared last week with Russian officials had been gathered by Israeli intelligence, according to U.S. officials familiar with the matter, a disclosure that could have far-reaching consequences for U.S. national security.

The intelligence—concerning terrorist threats against airliners—was meant for U.S. eyes only and was provided as part of a longstanding sharing agreement that is predicated on mutual assurances of secrecy, these people said.

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