Mr Scaramucci, who worked briefly for Mr Trump during his first term, said the US president's behaviour towards other world leaders was markedly different from the apparent deference he shows towards Putin. Speaking to investment platform
Saxo, Mr Scaramucci, who held the post for 11 days in 2017 and who has since evolved into a fierce critic, claimed: "I think there is a compromise. I don't know exactly what it is. I don't know exactly, but Trump acts like it's not 'I'm having a love affair with this strong man,' it's not that. And it's not 'I too want to be a strong man' and 'I love the strong man.' Vladimir Putin's got something on him."
He continued: "Trump acts fearfully in relation to Putin. He's not cautious when it comes to other leaders. He's not when it comes to Trudeau.
"He's not cautious about Starmer. He's very cautious around Putin. I think there's a compromise there. There is a grip that the Russians have on Donald Trump. I don't know what it is, so I'm not going to speculate."
Reacting to a wave of Russian missile strikes on Kyiv, which killed at least 34 people and injured dozens more, Mr Trump wrote: "I am not happy with the Russian strikes on KYIV.
"Not necessary, and very bad timing. Vladimir, STOP! 5,000 soldiers a week are dying. Le'ts get the peace deal DONE!"
The wording raised eyebrows, with foreign policy experts highlighting Mr Trump's decision to address the Russian leader by his first name - a level of familiarity rarely seen between heads of state.
Critics also questioned why the President, who has regularly talked up his tough approach to global rivals, appeared to issue a pleading, almost personal appeal rather than a strong condemnation.
Mr Trump's choice of language - urging Mr Putin to "STOP" and describing the attacks as "not necessary" - stood in sharp contrast to statements from other Western leaders, who openly condemned the strikes as a brutal escalation.
The US President has not elaborated further on his message or commented publicly about the scale of the casualties.
Despite repeated denials from Mr Trump and his allies that there is any undue influence, Mr Scaramucci suggested the US President's conduct continues to indicate otherwise.
He said: "When you look at his interactions with other leaders, he's often aggressive, dismissive, even insulting. You don't see that with Putin. You see hesitation, you see caution. That's not accidental."
Since returning to office following his 2024 election victory over Joe Biden, Mr Trump has promised to bring the war in Ukraine to a "swift end," although he has provided few details on how he intends to achieve this.
He has also hinted that US military support for Kyiv could be reduced or withdrawn under his leadership, stoking fears among NATO allies.
Mr Trump's latest comments have fuelled speculation that he may be positioning the United States to broker a peace deal that favours Russia, or at least reduces pressure on Moscow.
Mr Scaramucci said: "There's a reason he's so careful with Putin. It's not loyalty, it's not ideology.
It's fear."