Democrat firebrand Ted Lieu has blamed Donald Trump for Alexei Navalny's death in a Russian gulag during an eyebrow-raising interview. 

The California Rep. floated the theory with MSNBC host Alex Witt the penultimate president's comments about NATO emboldened the Kremlin killing. The host offered little pushback as the congressman made his comments. 

Trump claimed he would encourage Russia to attack NATO members who didn't pay their share of the alliance's budget while speaking at a rally last weekend. 

Navalny, the strongest opposition leader facing Putin, was killed aged 47 at a penal colony known as the 'Polar Wolf' in Siberia on Friday. 

'It's quite a coincidence,' Lieu said of the timing, adding that 'Russia certainly was listening' to Trump and he gave them the 'green light to do all sorts of crazy stuff.'

Lieu's comment came after Witt brought up Navalny's death and President Joe Biden's response saying that Putin was responsible.

'What are your thoughts about this and how, if we can, should the US hold Russia responsible?' she asked. 

'I think we have to ask ourselves, why did Navalny all of a sudden die at this point in time?' Lieu said. 

'I first of all, agree with President Biden that Russia is responsible for his death. Also, what happened in a few days leading up to his death?

'Well, we had former President Donald Trump essentially say that Russia should attack European countries.'

Trump bragged to a MAGA rally in Conway, South Carolina, that if NATO allies had failed to pay their bills, the US would not defend them from Russia. 

'In fact I would encourage them to do whatever the hell they want,' Trump said. 'You gotta pay. You gotta pay your bills.'

Lieu condemned this as 'crazy, traitorous language'.     

'Russia certainly was listening, and I think they thought, hey, we now have a green light to do all sorts of crazy stuff,' Lieu said.

Witt asked him whether he was suggesting that there could be 'a direct link' between Trump's comments and Navalny's death.  'Do you think it emboldened, potentially, Putin?' she asked.   

'I think it's quite a coincidence,' Lieu replied. 'And certainly Russia is listening to what the former president is saying. He's saying crazy stuff.'

In stark opposition to other Western world figures, Trump also failed to condemn Navalny's untimely death despite speaking at several more events this weekend. 

Republican presidential hopeful Nikki Haley slammed his response as 'bone-chilling' and said it showed him 'siding' with Putin.  

Navalny died while serving a 19-year sentence on charges which have been widely recognized as politically motivated. 

Along with his Anti-Corruption Foundation, he has been the main opposition figure against Putin for the past decade. 

Russia's prison service claimed the courageous leader died from 'sudden death syndrome' after collapsing. Signs of bruising were reportedly found on his body.  

'Make no mistake, Putin is responsible for Navalny's death,' President Joe Biden said in a statement from the White House.

'Even in prison he was a powerful voice for the truth,' Biden continued, with US Vice President Kamala Harris adding the death was 'a sign of Putin's brutality.'

Navalny's wife, Yulia Navalnaya shared a touching photo of them together in happier times in a heartbreaking social media post. 'I love you,' she wrote.