President Donald Trump is pushing back on talk by some House Democrats of impeaching him.

Trump asked in a tweet Friday: "How do you impeach a president who has won perhaps the greatest election of all time, done nothing wrong" and has had the "most successful two years of any president.”

House Speaker Nancy Pelosi has been cautious about whether her new Democratic majority would ever impeach Trump, but at least two of her members are ready to move forward.

California Rep. Brad Sherman and Texas Rep. Al Green introduced articles of impeachment against Trump on Thursday, the first day of the new Congress.

Trump says his campaign did not collude with Russia during the 2016 election, which is a focus of special counsel Robert Mueller's investigation.