House Democrats prosecuting U.S. President Donald Trump's impeachment trial used their final day of opening arguments to accuse the commander-in-chief of staging a cover-up to hide his illegal and corrupt requests to Ukraine.

The managers focused their efforts on prosecuting the second of two charges the House passed in December against the president -- obstruction of Congress. The case against Trump is centered on it and an abuse of power article, both of which stem from Trump's multiple requests to Ukraine to declare criminal probes into leading Democratic candidate Joe Biden, and his subsequent decision to refuse to cooperate in the congressional probe into the matter.

"At the heart of Article 2, obstruction of Congress, is a simple, troubling reality: President Trump tried to cheat. He got caught. And then he worked hard to cover it up," congressman Hakeem Jeffries, one of seven House lawmakers prosecuting the case, said from the well of the Senate. "President Trump was determined to carry out his corrupt scheme."

Prosecutors had on Thursday zeroed in on abuse of power, saying that Trump's repeated requests that Ukraine declare the investigations were founded squarely in his personal interests to win re-election, not to root out corruption.

The president's conduct, congressman Jerry Nadler said, "captures the worst fears of our founders and the framers of the Constitution."

The abuse of power article is centered on Trump's decision to hold up millions of dollars in security assistance to Ukraine as well as a coveted Oval Office meeting sought by President Volodymyr Zelensky while he was pushing to have the probes declared.

The military aid was only released after the president's hold on it became public, and after the House of Representatives launched its investigation, Jeffries said.

"The $391 million in security aid was only released because President Trump was caught red handed. The actions of President Trump and high-level White House officials allowed his abuse of power to continue beyond the watchful eye of Congress, and most importantly, the American people," the lawmaker charged.

The president has denied any sort of wrongdoing took place.

Trump's team is expected to bring up their case beginning Saturday, and some reports have said senators are considering an abbreviated session that day which would begin in the morning as Chief Justice John Roberts, who is presiding over the proceedings, will not have any duties over the weekend at the Supreme Court.

Trump lawyer Jay Sekulow told reporters on Capitol Hill on Thursday the president's team "will be putting on a vigorous defense of both facts and rebutting what they've said."