President Donal Trump’s phone call with the U.S. Ambassador to the European Union Gordon Sondland may have been overheard or intercepted by numerous intelligence agencies, including the Russians, experts said.

The call, which was made by Sondland from Ukraine, while he was at a restaurant, raises serious counterintelligence concerns and appears to be a security breach as there was a high possibility of intelligence agencies from Russia and other countries listening in on the call, CNN reported.

According to Marc Polymeropoulos, a former CIA officer who oversaw operations in Europe and Russia, the call between Sondland and Trump was an “egregious violation of traditional counterintelligence practices” which officials like Sondland are made aware of.

"I cannot remember in my career any time where an ambassador in a high counterintelligence environment like Kiev would have such an unsecure conversation with a sitting president. This just should not happen," Polymeropoulos said. "There is little doubt that the Russians and perhaps multiple other foreign intelligence services would have intercepted this call. Moscow undoubtedly would have been pleased."

It is not known whether Sondland’s phone was encrypted at the time of the call. However, according to current and former government officials, such protection is not usually available on the phone of a U.S. diplomat.

"Why a president is talking to an ambassador on a non-encrypted telephone is crazy for today's age, and worse in public," said Todd Carroll, a former FBI official. "Ukraine is one of the most open areas for intelligence agencies to work in. Both sides. I was told when I was there in 2010 that expect all your calls to be monitored."

The phone call that was made on July 26, was revealed by Bill Taylor, the top U.S. diplomat in Ukraine, during his public testimony on Wednesday. He said that one of his staff members had ‘overheard’ Sondland talking from his cell phone to President Trump about the ‘investigations.’

For Democrats, this new information adds further proof to the fact that the top U.S. officials not only engaged in an alleged quid pro quo but also disregarded the security protocols.

Chairman of the Joint Chiefs of Staff Army General Mark Milley (R) listens while US President Donald Trump speaks before a meeting with senior military leaders; US troop levels in northern Syria will probably stabilize around 500, according to Milley
Chairman of the Joint Chiefs of Staff Army General Mark Milley (R) listens while US President Donald Trump speaks before a meeting with senior military leaders; US troop levels in northern Syria will probably stabilize around 500, according to Milley AFP / Brendan Smialowski