US intelligence officials have warned their Israeli counterparts that President-elect Donald Trump’s ties to Russia could pose a security threat, since information passed on to his administration may reach Moscow and from there be leaked to Iran, a Hebrew-language daily reported Thursday.

During a recent meeting between US and Israeli intelligence staff, the Americans also assessed that Russia has some kind of leverage over Trump, but did not go into details, the Yedioth Ahronoth newspaper claimed, citing unidentified Israeli officials who were present at the session.

The report did not specify when or where the meeting took place, or who was present, and there was no independent confirmation of the claims.

Israel and the US have a history of intelligence teamwork that increased during the early 2000s and culminated in 2008 with a formal agreement for full cooperation and sharing of information sources.

US representatives also told the Israelis that they had reliable information “of the highest level” that Russian intelligence agents were behind the hacking of the email accounts of the Democratic National Committee and individual Democrats during the US elections last year, the report said. Publication of the emails was seen as damaging to Democrat nominee Hilary Clinton.

Russian President Vladimir Putin (L) and ExxonMobil CEO Rex W Tillerson, Trump's pick for secretary of state, at a ceremony to present awards to the heads and employees of major energy companies in Saint Petersburg on June 21, 2013. (AFP PHOTO /SPUTNIK/Michael Klimentyev)

Russian President Vladimir Putin (L) and ExxonMobil CEO Rex W Tillerson, Trump’s pick for secretary of state, at a ceremony to present awards to the heads and employees of major energy companies in Saint Petersburg on June 21, 2013. (AFP PHOTO /SPUTNIK/Michael Klimentyev)

In the meeting, the Americans indicated to Israel they should be cautious in sharing information with the White House or the NSA after January 20 — the day of Trump’s inauguration — until the next administration has shown itself to be beyond suspicion of compromising ties with Russia, a close ally of Israel’s regional nemesis Iran.

The Yedioth report came two days after media reports of a dossier circulating in Washington which alleges that Trump’s aides colluded with the Kremlin ahead of the US election, and that Russia has compromising information of a sexual nature about Trump. The incoming president has stridently denied the allegations.

American media and politicians have been in possession of versions of the 35-page report for months but, unable to corroborate its claims, had declined to publish it.

On Tuesday, after several media outlets reported that Trump had been briefed on the allegations circulating about him, the BuzzFeed news site took the controversial step of publishing the dossier in full — while admitting it was “unverified.”

The dossier includes unsubstantiated claims that the Russians possess videos involving prostitutes, filmed during a 2013 visit by Trump to a luxury Moscow hotel for the Miss Universe contest, supposedly as a potential tool for blackmail.

It also alleges that Trump advisers including his lawyer Michael Cohen maintained regular contact with Russian officials and others linked to Russian intelligence during the election and have been exchanging information for “at least” eight years.

On Friday US intelligence chiefs, briefing Trump on allegations of Russian interference in the election, reportedly included a two-page summary of the most credible claims from the dossier.

That classified summary has been shown only to Trump, US President Barack Obama, and a group of senators from the Senate Intelligence Committee.

Trump angrily dismissed the report as a fabrication, telling a news conference: “It’s all fake news. It’s phony stuff. It didn’t happen.”

And he slammed US intelligence for allowing the information to leak.

“I think it was disgraceful — disgraceful that the intelligence agencies allowed any information that turned out to be so false and fake out,” Trump charged. “I say that that’s something that Nazi Germany would have done.”

AFP contributed to this report.