The president was asked what he thought about the effort as he arrived back at the White House from a weekend in Delaware on Sunday.
He smiled, then simply offered three words: “Lots of luck!”
McCarthy opened the inquiry last week, claiming GOP lawmakers have “uncovered serious and credible allegations” against Biden.
But if that evidence exists, it hasn’t been made public ― and even some Republican lawmakers are skeptical.
Rep. Ken Buck (R-Colo.), a staunch conservative and member of the right-wing Freedom Caucus, said last week that impeachment proceedings should begin only when there’s evidence of high crimes and misdemeanors.
“That doesn’t exist right now,” he said on MSNBC.
The White House slammed McCarthy.
“He vowed to hold a vote to open impeachment, now he flip-flopped because he doesn’t have support,” White House spokesman Ian Sams said last week. “This is extreme politics at its worst.”