The co-founders of opposition research firm Fusion GPS — which backed the infamous Russia dossier from an ex-British spy about Donald Trump — warned Rudy Giuliani on Sunday they would not let him "deliberately lie about us."
In an interview with NBC News' "Meet the Press," Glenn Simpson and Peter Fritsch said the research by ex-British spy Christopher Steele began "as an ordinary business investigation" — that initially was paid for by Republicans, and later by the Democratic National Committee and Hillary Clinton's presidential campaign.
But the blowback has taken a toll — particularly that of Guiliani.
"I want to put him on notice that we're just not going to let him deliberately lie about us," Simpson said.
"Let's be clear, he's not confused. He's deliberately lying. We're going to respond when someone is deliberatey lying, especially the lawyer of the president."
In a scathing opinion piece in The New York Times on Friday, the pair laid into Giuliani.
"Mr. Giuliani, the president’s personal lawyer and the main stirrer of the conspiracy pot in Ukraine, cooked up a fresh fabrication just this week, telling Glenn Beck on his TV program that he had 'very strong evidence that a lot of the Steele dossier was produced in Ukraine' and that 'Glenn Simpson spent a fair amount of time there during the time that the dossier was being written.'"
Fritsch said it has been "unpleasant" when the pair had been "forced to be silent on our role" when opponents are "pushing lies about you."