Former Central Intelligence Agency Director Michael Hayden isn’t ready to say there’s a direct link between Russia and President Trump or his campaign — but, he says, “there’s a lot of smoke.”

“This does deserve an investigation because there are just so many coincidences,” Hayden told Yahoo News and Finance Anchor Bianna Golodryga on Monday.

Hayden, a critic of Trump during the campaign who has served in national security roles in Democratic and Republican administrations, said there seems to be a lot of what he would call “connective tissue between at least elements of the Trump campaign and people inside the Russian Federation — an unusual number.”

Hayden pointed out, for example, that Roger Stone — Trump’s longtime friend and a former campaign adviser — said he had a “back channel” to WikiLeaks founder Julian Assange. And late last summer, Stone said he knew that a batch of emails that were about to be released by WikiLeaks would be about Hillary Clinton’s former campaign chief, John Podesta, before they were leaked.

“I don’t think that’s good,” Hayden said. “It may not be criminal, but it does raise questions.”

So, too, does Trump’s “absolute refusal during the campaign to say anything even modestly critical” about Russian President Vladimir Putin, Hayden said.

Hayden, who has also served as director of the National Security Agency and as principal deputy director of national intelligence, further criticized Trump’s evidence-free assertion that his phones were wiretapped by former President Barack Obama before the election.

Related: Without evidence, Trump accuses Obama of wiretapping Trump Tower

“Barack Obama could not authorize this. It had to go through the courts,” he said. “If this happened, if some sort of warrant were granted, I’m not even sure that the president would know.”

To obtain such a warrant — known as a Foreign Intelligence Surveillance Court Act order, or FISA — the FBI, NSA or CIA would have to prove to a judge that the target of the surveillance was either “an agent of a foreign power, or involved in criminal activity.”

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“If those are your options, that can’t be good news for the administration,” Hayden said.

Hayden noted that both FBI Director James Comey and former Director of National Intelligence James Clapper denied any suggestion that communications at Trump Tower were wiretapped before the election.

“You have two sources of FISA warrants saying, ‘Nah, we didn’t do this,’” Hayden said. “Wow.”

Then why would Trump tweet such an explosive accusation?

“I honestly, genuinely don’t know,” Hayden replied.

Earlier Monday on MSNBC’s “Morning Joe,” Hayden said he believes Trump’s tweeted wiretapping claim was strategic. The president had a rocky couple of days in which his attorney general, Jeff Sessions, weathered a firestorm over undisclosed communications with Russia’s ambassador during the campaign.

“He’s trying to detract attention from what was a very, very, bad news cycle,” Hayden said. “The president of the United States put his reputation, the reputation of his predecessor, and the reputation of this nation at risk to get at least a ‘draw” out of the next 24 hours.”

The former CIA chief said Trump needs to realize members of the intelligence community “really want to serve him — they are not his opposition.”

“They want to go out and collect intelligence to make the president of the United States … as wise as they can make him,” Hayden told Yahoo News.

But Trump can expect some blowback from the intelligence community because of his wiretap attack, Hayden said.

“They’ve gone to battle stations,” he said. “They’re going to push back on that story if only in their own self-defense, because what the president has accused them of — it’s called a felony.”

Also read: Ex-CIA director: Trump apparently ‘forgot that he was president’

During the wide-ranging interview, Hayden suggested the sanctions placed on Russia by the U.S. in response to Moscow’s meddling in the U.S. presidential election were too narrow — and too soft.

“Don’t think of this as a cyber-problem,” Hayden said. “Don’t even think of it as an election problem. I think you need to think of it as a Russia problem.”

“I think our response to this shouldn’t be narrowly confined to … [expelling] some Russian diplomats or denying them some vacation spots on the Eastern Shore,” he continued. “I think we should look at the broad sweep of American relations.”

Hayden suggested three possible actions the Trump administration could take against Moscow: provide defensive arms to Ukraine, give oil to European allies to reduce their dependence on Russian energy, and unleash a U.S. cyberattack on the Kremlin.

“We have it in our ability to use cyber weapons to erode Russian autocracy,” Hayden said. “I would shove as many anonymizing tools as I could develop and get into the Russian cyberspace to make it more difficult for the Russian state to monitor their own people.”

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