Rep. Eugene Vindman, D-Va., said he is "not afraid" after the Department of Defense asked the U.S. House to investigate his Ukraine work.

"Donald Trump and Pete Hegseth just launched a sham investigation into me for my support for Ukraine, all because I demanded Trump’s call transcripts with Saudi Crown Prince Mohammed bin Salman be released.  Instead of transparency, I was met with retaliation," he wrote on X on Friday.

"This sham investigation went to the Ethics Committee almost immediately after I spoke on the House floor, demanding that Trump release his shocking transcripts with MBS. Let’s be clear: this is nothing more than Trump trying to exact revenge. Here’s the thing: I’m not afraid," he added.

In a letter from Nov. 19, the Pentagon's General Counsel Earl Matthews alleged that Vindman and his twin brother Alex were acting as “paid brokers” for American defense firms without U.S. government approval. Matthews alleged that they were seeking contracts with Ukraine after Russia’s invasion in 2022.

The brothers served on the National Security Council when Trump was first impeached in 2019.