The report, authored by Politico’s Daniel Lippman, cited three former US officials with knowledge on the matter, “several of whom served in top intelligence and national security posts”, it said.

According to Politico, the Israelis planted International Mobile Subscriber Identity (IMSI) catchers —known in technical-surveillance lingo as “StingRays” after a leading hardware brand. StingRay devices are designed to simulate the activity of legitimate cell towers in order to trick cell phones into communicating with them. That allows StingRay users to monitor the physical whereabouts of targeted cell phones. Some of the more expensive Stingray models can intercept the actual content of telephone conversations and can even plant Trojans on the compromised phones of unsuspecting users.

Politico said that the StingRays found around the White House were of the highest technical sophistication, and were “likely intended” to spy on President Trump, his senior advisers and other close associates. Politico said it had no information on whether the attempt was successful. The spy devices were detected by the Department of Homeland Security (DHS) in 2017 and acknowledged by US government officials in 2018. Senior American intelligence officials allegedly told Politico that an exhaustive two-year investigation into the matter showed “with confidence [that] the Israelis were responsible” for the StingRays.

The investigation was led by the counterintelligence division of the Federal Bureau of Investigation with the help of the DHS and the Secret Service. The National Security Agency and the Central Intelligence Agency are also known to assist such counterintelligence investigations. The devices were disassembled and their technical specifications were carefully inspected to assess their history and origins. Investigators reportedly concluded that very few countries have the technical and financial capabilities to build and plant such devices in the US, and that Israel was the most likely culprit.

Politico also said that some intelligence officials are unhappy about the Trump administration’s lack of response to the alleged spying by Israel. According to the officials, the White House did not file a protest —either publicly or privately— with the Israeli government, and “there were no consequences for Israel’s behavior”.  On Thursday afternoon, the US president voiced skepticism when asked by reporters about the Politico report: “I really would find that hard to believe”, said Trump, adding that his “relationship with Israel has been great”. Meanwhile the office of the Israeli Prime Minister Benjamin Netanyahu dismissed the Politico report as “a blatant lie” and noted that Israel’s spy services had “a directive from the Israeli government not to engage in any intelligence operations in the US”.