Democrats unveiled two impeachment charges against US President Donald Trump Tuesday, accusing him of abuse of power and obstruction in pressuring Ukraine to help him attack his 2020 election rivals.

The charges, if approved by the House of Representatives in a vote expected next week, would make Trump only the third US president to be impeached and placed on trial in the Senate.

"Our president holds the ultimate public trust," said Jerry Nadler, chairman of the House Judiciary Committee.

"When he betrays that trust and puts himself before country, he endangers the constitution, he endangers our democracy and he endangers our national security."

Speaker of the House Nancy Pelosi (C), flanked by House Judiciary Chairman Jerry Nadler, and House Oversight Committee Chairwoman Carolyn Maloney, announces articles of impeachment against President Donald Trump on December 10, 2019
Speaker of the House Nancy Pelosi (C), flanked by House Judiciary Chairman Jerry Nadler, and House Oversight Committee Chairwoman Carolyn Maloney, announces articles of impeachment against President Donald Trump on December 10, 2019 AFP / SAUL LOEB

Adam Schiff, who as head of the House Intelligence Committee oversaw the investigation, said Trump's "continuing abuse of power" had left Democrats no choice.

"The evidence of the president's conduct is overwhelming and uncontested," he said.

Nadler said the Judiciary Committee would meet later in the week to consider the articles of impeachment.

The Democrat-led committee is expected to pass them and forward them to the full House next week. The Democratic majority will almost certainly vote them through, paving the way for a Senate trial, likely in January.

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