President Donald Trump's legal defence team strenuously denies that he has committed impeachable acts, denouncing the charges against him as a "brazen and unlawful" attempt to cost him re-election as House Democrats laid out in meticulous detail their case that he should be removed from office.

In the first legal filings for the Senate impeachment trial that opens in earnest on Tuesday (Wednesday AEDT), the duelling arguments from the White House and the House impeachment managers previewed a politically charged fight over Trump's fate, unfolding against the backdrop of the presidential election campaign.