Israel spied on closed-door nuclear talks between the United States and Iran last year in order to build a case against the impending deal, according to a Wall Street Journal report.

Prime Minister Benjamin Netanyahu's government reportedly sought to acquire information on the negotiations, in turn using said information to lobby members of Congress against a nuclear deal.

In addition to eavesdropping on closed-door talks, the report said, Israel “acquired information from confidential U.S. briefings, informants and diplomatic contacts in Europe.”

The White House discovered the operation when U.S. intelligence agencies spying on Israel "intercepted communications among Israeli officials that carried details the U.S. believed could have come only from access to the confidential talks.”

However, the Obama administration was far more concerned with Israel's alleged leaking of information to Congress in order to derail a potential deal.

“It is one thing for the U.S. and Israel to spy on each other," a senior U.S. official told the Journal. "It is another thing for Israel to steal U.S. secrets and play them back to U.S. legislators to undermine U.S. diplomacy.”

The report cited Israeli officials as saying that Netanyahu and Israeli Ambassador to the U.S. Ron Dermer knew the intervention would damage ties with the White House, but decided that was a tolerable cost.

Nevertheless, the campaign may have backfired, Israeli officials said, because it alienated congressional Democrats whose support was key to blocking the deal.

The report cited interviews with more than a dozen current and former diplomats, intelligence officials, policy makers and lawmakers in the U.S. and Israel.

Israel denied the "utterly false allegations."

"The state of Israel does not conduct espionage against the United States or Israel’s other allies," a senior official in the Prime Minister’s Office told the WSJ. "The false allegations are clearly intended to undermine the strong ties between the United States and Israel and the security and intelligence relationship we share.”