The US Speaker Nancy Pelosi has confirmed an impeachment inquiry into President Donald Trump.

Speaker Pelosi had previously stood against impeachment calls, arguing the move could bring a political backlash.

But she has this morning responded to growing calls for an impeachment inquiry to begin over President Trump’s apparent bid to find dirt from Ukraine over the son of his potential rival, Joe Biden.

Mr Trump has admitted in a July phone call with the Ukraine president, he discussed Joe Biden in the context of fighting “corruption” in the country.

This has prompted significant concerns around the potential pressuring of a foreign leader to investigate a domestic political opponent.

There are allegations that Mr Trump has promised $300 million of American investment in Ukraine in exchange for a corruption investigation into Joe Biden and his family.

There has never been any evidence of wrongdoing by Mr Biden nor his son.

“It’s really sad to think the president would perform an impeachable offence, it’s hard,” Speaker Pelosi said.

Mr Biden has now come out in support of impeachment efforts unless President Trump provides a full account of his telephone call with the Ukrainian leader.

The US President says he will release unredacted audio of the phone conversation, but has not yet done so.

In order for Mr Trump to be impeached, the action must pass both the House of Representatives and the Senate.

If the investigation finds cause to continue, it will be the fourth time in American history action has been taken to impeach a president, but no American leader has ever actually been impeached.

There are some fears the impeachment inquiry could galvanise support for Mr Trump.

“Clinton was actually impeached by the House of Representatives and went on to win the election,” Chris Ulhmann, Nine News Political Editor, told 3AW’s Tony Jones.

“I think that’s something that does concern some Democrats, that this might play straight into Donald Trump’s hands.”

The President has slammed the investigation, labelling it as “harassment”.

PRESIDENTIAL HARASSMENT!

— Donald J. Trump (@realDonaldTrump) September 24, 2019

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(Photo by SAUL LOEB/AFP/Getty Images)