The U.S. House of Representatives on Tuesday launched an official impeachment investigation of President Donald Trump following reports he encouraged a foreign leader to conduct a probe that could damage a political rival.

House Speaker Nancy Pelosi, a Democrat, announced the investigation at a news conference, declaring "no one is above the law."

There has been a groundswell of support among Democratic lawmakers for the move following Trump's admission that he asked Ukraine President Volodymyr Zelenskiy to investigate the son of former Vice President Joe Biden, a leading presidential candidate.