Heated exchanges ensued between former President Donald Trump and President Joe Biden during the CNN Presidential Debate on Thursday night, as the two rivals went head-to-head during their second debate since 2020. 

Illegal immigration, abortion, and inflation were among the top issues on the debate stage, as well as climate change and the Israel-Hamas and Russia-Ukraine wars.

The debate comes as Biden and Trump are the frontrunners for the Democratic and Republican parties respectively. This is the first televised debate between the candidates for this election cycle and a second hosted by ABC is scheduled to be held in September. 

Trump did not participate in the Republican primary debates, while the Democratic National Convention (DNC) threw its full support behind Biden and did not hold any debates among his challengers.

BIDEN CAMP DODGES ANSWERING IF PRESIDENT PLANS TO USE PERFORMANCE-ENHANCING DRUGS BEFORE DEBATE

President Biden and former President Trump.  ((AP Photo/Julia Nikhinson and Evan Vucci))

Here are the top clashes from Thursday's debate:

1. "I really don't know what he said," Trump-Biden immigration clash

When CNN moderator Jake Tapper asked President Joe Biden to inform voters why he can curb the record-high numbers of illegal migrants crossing the border during Thursday night's debate, Biden and Trump sparred over their immigration policies, which ended in Biden calling Trump a "liar" and Trump appearing to not understand a portion of Biden's responses.

After touting Congress's bipartisan border package that lawmakers bucked earlier this year, Biden said "we find ourselves in a situation where when he was president, he was separating babies from their mothers put them in cages, making sure that the families were separated."

"That's not the right way to go. What I've done since I've changed the law, what's happened? I've changed it in a way that now you're in a situation where there are 40% fewer people coming across the border illegally, that's better than when he left office. And I'm going to continue to move until we get the total ban on the total initiative relative to what we can do with more Border Patrol and more asylum officers," Biden said.

But Trump, appearing to not understand Biden, responded: "I really don't know what he said at the end of that sentence, I don't think he knows what he said either."

"Look, we had the safest border in the history of our country," Trump continued. "All he had to do was leave it, all he had to do was to leave it. He decided to open up our border, open up our country, to people that are from prisons, people that are from mental institutions, insane asylum, terrorists – we have the largest number of terrorists coming into our country right now."

TRUMP, BIDEN SPAR OVER GOLF HANDICAPS AS THEY TRY TO CONVINCE VOTERS THEY ARE NOT TOO OLD FOR THE PRESIDENCY

US President Joe Biden speaks as he participates in the first presidential debate of the 2024 elections with former US President and Republican presidential candidate Donald Trump at CNN's studios in Atlanta, Georgia, on June 27, 2024. (Getty Images)

2. ‘Alley cat morals,’ Trump-Biden clash over Stormy Daniels allegations

Biden accused former President Trump of "having sex with a porn star" and said he has "the morals of an alley cat," but the presumptive Republican nominee maintained that he did not, and accused Biden of being behind his legal cases because "he can't win fair and square." 

"How many billions of dollars do you owe civil penalties for molesting a woman in public? For doing a whole range of things—having sex with a porn star…while your wife was pregnant?" Biden said. "You have the morals of an alley cat during the night, sir." 

Trump fired back denying the allegations.

"I didn’t have sex with a porn star, number one," he said. "Number two, that was a case that was started, and they moved a high-ranking official—DOJ—into the Manhattan DA’s office to start the case." 

Trump was referring to Matthew Colangelo, who served as a senior DOJ official in the Biden administration, and left to join Bragg’s prosecution team. 

3. ‘I will have that war settled between Putin and Zelinsky as President-Elect before I take office,’ Trump-Biden spar over Ukraine-Russia war

Trump threw several jabs at Biden for giving billions of dollars to Ukrainian President Volodomyr Zelenskyy to continue its defense against the Russian invasion that began in February 2022 and said if elected, he'd have the war "settled" before taking office.

"He's given $200 billion, that's a lot of money," Trump said. "I don't think there's ever been anything like it. Every time that Zelinsky comes to this country. He walks away with $60 billion. He's the greatest salesman ever."

"The money that we're spending on this war, we shouldn't be spending. It should have never happened. I will have that war settled between Putin and Zelinsky as President-Elect before I take office on January 20. I'll have that war settled. People being killed so needlessly, so stupidly and I will get it settled, and I'll get it settle fast before I take office."

In response, the current president said, "The fact is that Putin is a war criminal."

"He's killed 1000s and 1000s of people and he has made one thing clear, he wants to reestablish what was part of the Soviet empire, not just a piece, he wants all of Ukraine," he said.

"By the way, all that money we give Ukraine from weapons we make here in the United States, give them the weapons, not the money at this point, and I made our NATO allies produce as much funding for Ukraine as we have – that's why it's that's why we're strong," he said. 

A RASPY BIDEN GETS OFF TO A HALTING START AGAINST TRUMP IN THE FIRST 2024 PRESIDENTIAL ELECTION DEBATE

This composite image shows President Biden, former President Trump and the southern border. ((AP Photo/Gerald Herbert and Fox News))

4. Trump-Biden spar over cognitive abilities, golf handicaps: ‘You are a child’

During the CNN Presidential Debate, CNN moderator Dana Bash presented the age Biden and Trump would be at the end of a potential second term.

Biden would be 86. Trump would be 82. 

Biden defended his age, saying he "spent half my career being criticized about being the youngest person in politics. I was the second-youngest person ever elected to the United States Senate, and now I’m the oldest. This guy is three years younger and a lot less competent." 

But Trump reminded that he has taken two cognitive tests. 

"I aced both of them, as you know, we made it public. He took none. I’d like to see him take one. Just want a real easy one," Trump said. 

Trump, an avid golfer, said Thursday night that he recently "won two club championships—not even senior—two regular club championships." 

"To do that, you have to be quite smart and you have to be able to hit the ball a long way and I do it," Trump said. "He doesn’t do it. He can’t hit a ball 50 yards. He challenged me to a golf match—he can’t hit a ball 50 yards." 

"I’ve seen you swing. I know your swing," Trump fiered back. "Let’s not act like children." 

But Biden replied: "You are a child." 

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Debate dial shows Democratic voters react favorably towards Biden's comments on the economy.   (Fox News Digital)

5. Biden-Trump exchange jabs over criminal records

While Biden reminded Trump that the "only person" that has a felony record on the debate stage is Trump, the former president said "when he talks about a convicted felon, his son is a convicted felon."

"At a very high level, his son is convicted," Trump said, adding that he'd seek "retribution," referring to a potential November election victory. 

"As soon as he gets out of office, Joe could be a convicted felon with all of the things that he's done," he continued. "He's done horrible things, all of the death caused at the border, telling the Ukrainian people that we're gonna want a billion dollars if you change the prosecutor, otherwise, you're not getting a billion dollars. If i ever said that, that's quid pro quo."

"This man is a criminal. This man, you're lucky, you're lucky. I did nothing wrong. We have a system that was rigged and disgusting," Trump said.

Meanwhile, Biden pushed back at the idea that he has done any wrongdoing "is outrageous."

"It's simply a lie," Biden responded. "Number two, the idea that you have a right to seek retribution against any American just because you're president is wrong. No president has ever spoken like that before. No president in our history has spoken like that before." 

Fox News Digital's Brooke Singman contributed to this report.