Fox News veteran Brian Kilmeade got into a testy exchange with Fox & Friends Weekend cohost Rachel Campos-Duffy over Donald Trump's deal to import Russian diesel to the US this week.

Kilmeade, 62, was on the program to react to Trump's call for Ukraine to replace President Volodymyr Zelensky with another leader on Sunday.

Campos-Duffy maintained the Saturday remarks were a necessary response to Ukrainian attacks that have hurt global diesel supplies. She argued Ukraine's war approach was 'hurting President Trump and the administration.'

She asked Kilmeade to weigh in.

Kilmeade framed Trump's calls to replace Zelensky as a fit of frustration over the Ukrainian leader's Saturday condemnation of the diesel deal. The diesel itself, he said, was the start of a betrayal. 

'Do we tariff ourselves?' he joked, after flagging how the deal appeared to violate a bipartisan bill that allows the president to impose tariffs of up to 100 percent on Russian oil.  

He eventually warned the wife of Trump's transport secretary that Trump was potentially putting the US on the wrong side of history by siding with a man he saw as the 'modern' equivalent of Adolf Hitler – Russian President Vladimir Putin.

'Zelensky's frustrated because all this money will flow into Russia, who started this whole war, unprovoked. They are the bad guys,' he maintained. 

Campos-Duffy quickly pushed back.

'Are you saying that there were not peace efforts, that were not-,' she argued. 

Kilmeade interrupted: 'There's no plausible, practical peace effort that Vladimir Putin would participate in, effectively, that would end this war.'

As he spoke, Campos-Duffy attempted to interrupt. 

Kilmeade spoke over her: 'There's one person who is responsible. Vladimir Putin. That is it.'

As Campos-Duffy tried to get a word in still, Kilmeade proclaimed of Putin: 'And he's getting his a** kicked.'

Campos-Duffy, a Fox & Friends Weekend host since 2021, began to point out peace talks set up by Turkey and the United Nations in Russia and Ukraine to discuss a ceasefire surrounding the Black Sea.

'Boris Johnson advised Zelensky not to take the deal,' she told Kilmeade, before being immediately rebuffed.

'I don't know what Boris Johnson is doing now - is he in a retirement home?' Kilmeade quipped.

Cohosts Griff Jenkins and Charles Hurt repeatedly averted their eyes as the altercation became increasingly tense.

'No. No, but I think- I think that there's - there's a reason that the president is buying the- the- the- the diesel from Russia,' Campos-Duffy stammered. She said it was because of Zelensky's continued strikes on Russian refineries.

'Can you blame him,' Kilmeade stressed. Minutes before, Campos-Duffy suggested he was a 'big fan of Zelensky['s].'

'That's the war machine that's killing his people, that bombs apartment buildings,' Kilmeade argued.

'But he's dependent on us, and the president said don't do it,' Campos-Duffy hit back.

As Kilmeade started to answer, she asked, 'Are you for America or for-' before trailing off.

Kilmeade claimed the diesel shortage could be traced back to Iran and its attacks on Gulf States.

He called the 'new emphasis' Trump was putting 'on Russia' merely a distraction

'They'll be writing about this in war journals forever. The Ukrainians have modernized modern war before our very eyes,' Kilmeade said of Ukraine's continued use of drone warfare.

'I'm not so sure there's a positive, Brian,' a visibly unconvinced Campos-Duffy hit back. 'There are 30,000 young men on each side that are dying every single month,' 

Kilmeade had two words, this time. 'Vladimir Putin,' he stressed.

The two began to speak over each other at this point. Campos-Duffy claimed 'kids' in the Ukrainian army were being used 'as Guinea pigs' to advance the US's military.

'What kids?' Kilmeade asked, paving the way for another exchange.

'These are young men,' Campos-Duffy bristled at a point. 

'Rachel, this is a response to attacks,' Kilmeade continued. 'They're getting rocketed, so they found a way to out-.

Campos-Duffy interrupted to point out that Trump 'said he wanted peace in Ukraine' - to which Kilmeade said with a smile: 'Tell Vladimir Putin.'

She framed the Ukrainian leader as 'arrogant' and the reason for the lack of peace.

Kilmeade, at this point, blurted out: 'It would be the biggest mistake of his administration to work with Russia. That is a- that is the modern Hitler of our generation.

'He is the cause of all the problems in the region, and now is helping Iran kill our guys and blow up our bases,' Kilmeade concluded.

The moment was quickly clipped and went viral on Sunday.

The Ukrainian president also argued that the real source of rising energy prices was the Middle East war and disruption to shipping through the Strait of Hormuz.