WASHINGTON — The White House legal team has about 22 hours left as part of their opening arguments as they continue defending President Donald Trump, arguing he did "absolutely nothing wrong."

Now, Democrats are demanding that former National Security Advisor John Bolton testify after information is alleged to have come out.

The White House's defense team started making its case Saturday morning, spending two hours outlining its argument.

Team members said the president was genuinely concerned about corruption in the Ukraine, prompting the hold on military aid.

"Since the fall of the Soviet Union, Ukraine has suffered one of the worst environment for corruption in the world," said Mike Purpura of the White House defense team.

However, Democrats contend he withheld the aid to pressure Ukraine to announce an investigation into the former Vice President Joe Biden and his son Hunter Biden to help him politically ahead of Election day.

"They said, 'Oh, he's for fighting corruption elsewhere.' But no direct evidence that he said I want to cut off the aid to fight corruption," said Sen. Chuck Schumer, the Senate’s top Democrat.

The entire impeachment came from a July 25, 2019, phone call between Trump and Ukrainian President Volodymyr Zelensky. In the phone conversation, Trump asked for a "favor," according to an account provided by the White House. 

He wanted an investigation into both Democrats and the Bidens. Later it was revealed that the administration was also withholding $400 million in military aid from Ukraine.

Republicans argue the money was given to Ukraine without any investigation, and there was no quid pro quo, or favor for a favor.

Hunter Biden is accused of corruption while sitting on the board of a gas company based in Ukraine

One big thing to watch this week is whether the Senate will vote to call witnesses. 

The president's backers argue the Democratic case is weak in part because they rely on witnesses without firsthand knowledge.

Democrats contend people such as Bolton could help fill in some blanks.

Bolton writes in a forthcoming book that Trump told him he wanted to withhold hundreds of millions of dollars in security aid from Ukraine until it helped him with politically charged investigations, including into Democratic rival Biden.

Trump's legal team has repeatedly insisted that the Republican president never tied the suspension of military assistance to the country to investigations that he wanted into Biden and his son.

Bolton’s account was first reported by The New York Times and was confirmed to the Associated Press by a person familiar with the manuscript on the condition of anonymity to discuss the book, "The Room Where It Happened; A White House Memoir," ahead of its release March 17.

When the Times report went online Sunday night, the seven House Democratic managers immediately called on all senators to insist that Bolton be called as a witness and provide his notes and other relevant documents.

On Sunday, Trump tweeted that he never told Bolton that the aid to the Ukraine was tied to Democratic investigations.

On Monday morning, the president issued this tweet regarding Bolton being asked to testify.

Calling witnesses would require some Republicans to join with Democrats to vote in support of the subpoenas. 

After opening statements wrap up, senators will have a chance to question both sides, and then they will get to vote on witnesses.

The Associated Press contributed to this story.

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