President Donald Trump’s legal defence team has strenuously denied that he had 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, 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.

In a 46-page trial memorandum, and additional 60-page statement of facts, the House impeachment managers asserted that beginning in the spring, Trump undertook a corrupt campaign to enlist a foreign government to help him win the 2020 election. He did so, the Democrats argued, by pressuring Ukraine to publicly announce investigations of his political rivals, withholding as leverage vital military aid and a White House meeting for the country’s President.

In a six-page filing formally responding to the House impeachment charges submitted shortly after and filled with partisan barbs against House Democrats, Trump’s lawyers denounced the case as constitutionally and legally invalid, and driven purely by a desire to hurt him in the 2020 election.

“The articles of impeachment submitted by House Democrats are a dangerous attack on the right of the American people to freely choose their President,” they said in the response, which was Trump’s first legal submission in the impeachment proceeding, ahead of a fuller brief that is due on Monday. “This is a brazen and unlawful attempt to overturn the results of the 2016 election and interfere with the 2020 election, now just months away.”

The President’s lawyers did not deny any of the core facts underlying Democrats’ charges. But they said Trump broke no laws and was acting entirely appropriately and within his powers when he did so.

In a statement later in the evening, the House managers criticised the claim by the President’s legal team that the pressure on Ukraine was just Trump’s way of fighting corruption. “It is not,” the Democratic lawmakers wrote. “Rather it is corruption itself, naked, unapologetic and insidious.”