Friday on his nationally syndicated radio show, conservative talker Rush Limbaugh speculated that special counsel Robert Mueller’s probe into alleged Russian interference in the 2016 presidential campaign, and has expanded into an investigation of wrongdoing by Trump campaign operatives, has an ulterior motive.

Many have tried to compare Trump’s administration to that of Nixon during the Watergate scandal, but Limbaugh said the analogy of Watergate is more appropriate for the Obama administration.

According to Limbaugh, the Mueller probe has the purpose of covering up efforts by the Obama Department of Justice and FBI to taint Donald Trump’s presidency.