Lieu hinted in his response that the threat centered on his comments tying Nunes to Lev Parnas, a Soviet-born businessman and former associate of President Trump’s personal attorney Rudy Giuliani who is at the heart of the impeachment proceedings.

“I received your letter dated December 31, 2019 in which you state your client Congressman Devin Nunes will sue me if I don’t, among other actions, issue a public apology to Devin Nunes,” Lieu wrote in his own letter dated Thursday. “It is true that I stated Congressman Nunes worked with Lev Parnas and conspired to undermine our own government.”

“I welcome any lawsuit from your client and look forward to taking discovery of Congressman Nunes. Or, you can take your letter and shove it.”