Former CIA Director and retired Gen. David Petraeus says it is "unlikely" Israel will target Iranian nuclear sites in retaliation for last week's ballistic missile attack.

"It's publicly known that there are certain nuclear sites that they cannot deal with unless there's some really diabolically clever plan that would be very difficult to pull off without U.S. assistance," Petraeus said in an interview with CTV Power Play host Vassy Kapelos on Wednesday.

The debate over the scale of Israel's retaliation comes after Iran struck Israel with 181 ballistic missiles last week. Israel has pledged "serious consequences" for Iran – which backs militant groups like Hamas and Hezbollah – and how it does so could have major repercussions for the Middle East and the world.

U.S. President Joe Biden has voiced opposition to targeting Iranian nuclear sites and has also suggested Israel should refrain from attacking oil facilities.

Biden spoke to Israeli Prime Minister Benjamin Netanyahu on Wednesday for the first time in nearly two months.

According to White House press secretary Karine Jean-Pierre, the conversation was "direct" and "productive” but she declined to provide further details on whether Israel will give the Biden administration advance notice of any action it plans to take against Iran.

Israel's defence minister warned on Wednesday that his country's retaliation will be "lethal, precise and surprising."

When asked about that warning, Petraeus told Kapelos "I think it'll be all three of those things."

But Petraeus said he does not think even oil infrastructure will be targeted during this round of retaliation.

"I think they're going to see very significant strikes against a variety of military-related targets and infrastructure, and especially those that support Iran's nefarious actions supporting these maligned proxies," Petraeus said, going on to cite examples including Hamas and Hezbollah.

The former CIA director also told Kapelos "there is a greater risk" of a conventional war in the region.

"A lot is going to ride on how Iran responds to this particular Israeli retaliation," Petraeus said. "If it continues to escalate, Israel has extraordinary capacity and capability. Iran needs to recognize that. I think they do."

Joly responds to Poilievre support for nuclear targets

Petraeus' comments come as Foreign Affairs Minister Mélanie Joly said Wednesday that Israel's response to Iran needs to be "proportionate."

Joly's comments followed Conservative Leader Pierre Poilievre doubling down on his support for Israel to pre-emptively strike Iran's nuclear sites.

"If Israel were to stop that genocidal, theocratic, unstable government from acquiring nuclear weapons, it would be a gift by the Jewish state to humanity," Poilievre said Tuesday.

Poilievre first voiced his support for that move on Monday at a commemorative event marking the one-year anniversary of Hamas' Oct. 7 attack against Israel.

"Israel must be able to prevent Iran from using nuclear weapons, if necessary," Poilievre said at the commemoration event. "That means proactively striking Iranian nuclear sites and oil installations to defund the terrorist regime."

When asked by reporters whether attacking nuclear sites is proportionate, Joly would only say "the President of the United States has already said that he's against it."

Joly also suggested Poilievre does not want stability in the Middle East.

"The problem with Pierre Poilievre is that using the term peace is a taboo for him," Joly said. "We all know that what is required right now in the Middle East is peace and stability. That's what people in Israel want. That's what people in Gaza want. That's what people in Lebanon want. People in the West Bank want."

Defence Minister Bill Blair said on Monday it would be "appropriate" for Israel to hit Iranian oil production facilities, but did not mention nuclear sites.

But in a previous interview with CTV Power Play host Vassy Kapelos last week, Blair said both Iran's oil infrastructure and nuclear sites should not be targeted.

The federal government has condemned Iran's attack against Israel and expressed support for Israel to defend itself, but has said the international community must do everything it can to help avoid a bigger regional war.

NDP foreign affairs critic Heather McPherson also called out Poilievre for his stance in a social media post to X and referred to him as a "warmonger."

"Poilievre has no regard for civilian lives that would inevitably be lost in a wider war," McPherson wrote.

"This is a time for de-escalation, not further aggression. Poilievre is an agent of chaos and cannot represent Canada on the world stage."