Retired Army Lt. Col. Alexander Vindman argued that former President Trump’s recent comments about NATO are likely a “contributing factor” in the death of Russian opposition leader Alexei Navalny.

“Donald Trump invited Vladimir Putin to attack NATO. I would say that that probably was a contributing factor in the calculus around the assassination of Navalny,” Vindman told MSNBC’s Michael Steele Friday.

Vindman’s comments come just a week after Navalny died in prison. The Biden administration has blamed Russia’s government for the death, but Russia has said he died of natural causes.