US President Donald Trump’s explosive allegation that then-president Barack Obama wiretapped him during the 2016 election campaign is “plausible” since it has taken place during previous US administrations, an American political analyst in Virginia says.

“It’s entirely credible and entirely possible and believable that the Obama administration, or at least the deep state elements that are part of the national security apparatus like the NSA, the FBI, the CIA, it could be that those organizations, the intelligence services were monitoring Donald Trump throughout the campaign,” said Keith Preston, director of attackthesystem.org.

“No evidence has been presented that that actually happened, but it’s certainly plausible, it’s certainly possible,” Preston told Press TV on Saturday.

“Certainly, there has been examples of that happening previously in American politics,” he added.

On Saturday, Trump accused his predecessor of intercepting his communications at his offices in Trump Tower in New York City before the presidential election last year.

Trump offered no evidence to support his accusations, which were made during a Saturday morning tweet.

“Is it legal for a sitting President to be ‘wire tapping’ a race for president prior to an election? Turned down by court earlier. A NEW LOW!”

Trump did not provide any information to back up his claim, but went on to say, “I’d bet a good lawyer could make a great case out of the fact that President Obama was tapping my phones in October, just prior to Election!”

The president has also linked his predecessor to a major scandal, which has engulfed his administration regarding alleged contacts with Russian officials

An Obama spokesman rejected Trump’s claims as “simply false.”.

Experts say electronic surveillance of a US citizen by American intelligence agencies would require a warrant approved by a FISA court judge.  Presidents do not have the authority to order such wiretaps and would not even be aware of them as a routine matter.

If the president were involved in the process, it would be “scandalous and unheard of,” said Ron Hosko, a former assistant FBI director. Hosko called the allegations “unprecedented“ and “unlikely to have occurred in the very broad way” that Trump described.