In a revelation that is bound to further erode an already tense relationship between the U.S. and Israel, senior officials at the White House have learned Israel has been spying on nuclear talks with Iran — and then using the inside info to lobby members of Congress to kill the deal.

That’s according to a Wall Street Journal report, in which those officials say the spying began after the US and other interested parties entered negotiations on slowing down Iran’s nuclear program last year.

The revelation comes after a tumultuous few weeks, following Israeli Prime Minister Benjamin Netanyahu’s address to a joint session of Congress. In that address March 3, Netanyahu passionately declared the emerging agreement with Iran was a “bad deal.”

The WSJ report cites “current and former” White House officials who say Israel’s spying activity was an attempt to “penetrate the negotiations and then help build a case against the emerging terms of the deal.”

This has apparently upset some of the officials who have knowledge on the ongoing negotiations.

From the Journal:

“The espionage didn’t upset the White House as much as Israel’s sharing of inside information with US lawmakers and others to drain support from a high-stakes deal intended to limit Iran’s nuclear program, current and former officials said.”

President Barack Obama has said there is “nothing new” about Israel’s position regarding talks with Iran, telling the Associated Press “Netanyahu’s alternative to the talks amounts to no deal at all”

Still, the latest wrinkle in the matter has not done well to get the US and Israel closer to a consensus. The Journal cites one senior US official who lays a out a clear point on Israel’s tactics: “It is one thing for the U.S. and Israel to spy on each other. It is another thing for Israel to steal U.S. secrets and play them back to U.S. legislators to undermine U.S. diplomacy.”

Israel denies that it was spying on the talks.

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