Israeli Prime Minister Benjamin Netanyahu has flatly denied a report that his country was spying on the US.
A Politico article cites three former senior US officials who say Israel was likely behind surveillance devices found near the White House.
But a statement from Mr Netanyahu's office said this was "a blatant lie".
"There is a longstanding commitment, and a directive from the Israeli government not to engage in any intelligence operations in the US."
BBC reporters have contacted the state department for comment.
Israel is days away from a general election, with Mr Netanyahu fighting to hold on to his office.
What does the Politico report say?
The allegations appeared in an exclusive story for US news site Politico on Thursday.
International mobile subscriber identity-catchers (IMSI catchers) – informally known as StingRays – were reportedly found near the presidential residence and by other sensitive sites across Washington DC during the Trump presidency.
These devices act like mobile phone towers, tricking phones into sending their location, identity information, and even call contents and data usage.
One of the former officials who spoke anonymously to the site said the StingRays were likely designed to spy on President Trump. He said it is not clear if they succeeded.
FBI counterintelligence agents conducted analysis to find out where they came from. "It was pretty clear that the Israelis were responsible," a former senior intelligence official told Politico.
This same official also criticised the Trump administration, saying they did not publicly or privately reprimand the Israeli government for the alleged spying.
"I'm not aware of any accountability at all," the former official said.