Sen. Chris Murphy corrected himself shortly after saying he does not know if Secretary of State Mike Pompeo is involved with Rudy Giuliani’s work for President Trump in Ukraine.

The Connecticut Democrat told CBS Face the Nation host Margaret Brennan that he did not know if Pompeo was directly involved in Giuliani’s work before correcting himself shortly afterward. Trump’s personal attorney and former mayor of New York City, Giuliani has been investigating potential corruption in former Vice President Joe Biden’s dealings with Ukraine during the Obama administration.