Washington, Mar 22 (IANS): A former head of the Central Intelligence Agency (CIA), John O. Brennan, has said that he thinks Russia might have some kind of compromising information on President Donald Trump.

His remark on Wednesday on MSNBC's "Morning Joe" set off furious speculation about whether the former spy chief was basing that assertion on inside information.

Brennan, who served as CIA director from 2013 to 2017, speculated that Russians "may have something on him personally" when he was asked if he thought Trump was afraid of Russian President Vladimir Putin, the New York Times reported.

"The Russians, I think, have had long experience with Trump and may have things that they could expose," he said.

Brennan was heading the agency when a dossier surfaced in 2016 claiming the Russians had compromising information on Trump.

His comments came the day after Trump congratulated Putin in a phone call for his re-election that raised new questions about the President's relationship with Russia.

Brennan also said that his comments were speculation based on Trump's words and deeds as well as how Putin's government operated at home and abroad -- and not on any inside knowledge.

"I do not know if the Russians have something on Donald Trump that they could use as blackmail," he told the New York Times.

"When asked the question, I have pointed out the perplexing submissiveness of Trump towards Putin -- despite continued evidence of malign Russian activities," Brennan said.

"I do not know why he refuses to call out Russia; that is a question that can only be answered by Trump."