President Donald Trump talks to reporters in the Oval Office of the White House, in Washington, July 9, 2019.
FILE - President Donald Trump talks to reporters in the Oval Office of the White House, in Washington, July 9, 2019.

WASHINGTON - U.S. President Donald Trump predicted Monday that special counsel Robert Mueller's congressional testimony this week about whether the U.S. leader tried to obstruct his investigation into Russian meddling in the 2016 U.S. presidential election will end badly for him and that he shouldn't even be testifying.

Moreover, Trump said, "I am not going to be watching Mueller."

"Highly conflicted Robert Mueller should not be given another bite at the apple," Trump contended on Twitter. "In the end it will be bad for him and the phony Democrats in Congress who have done nothing but waste time on this ridiculous Witch Hunt. Result of the Mueller Report, NO COLLUSION, NO OBSTRUCTION!"

Mueller is set to spend hours before two House of Representatives committees on Wednesday, answering questions about the 448-page report released in April that he and investigators compiled after their 22-month probe.

Trump has long disparaged the investigation, but most Americans have not read the document. Mueller has said he will not offer opinions in his congressional testimony beyond what is in the report, which concluded that Trump had not colluded with Russia to help him win the election, even though his campaign had numerous contacts with Russia.

FILE - Robert Mueller, then-special counsel probing Russian interference in the 2016 election, departs Capitol Hill following a meeting with lawmakers, in Washington, June 21, 2017.

Mueller reached no conclusion whether Trump obstructed justice by trying to thwart the investigation, in part because of a Justice Department policy prohibiting charges against sitting U.S. presidents. However, Attorney General William Barr and then Deputy Attorney General Rod Rosenstein concluded that no criminal charges were warranted against Trump.

Opposition Democrats, however, are hopeful that Mueller's testimony will give visual credence to the often dry, legal statements contained in his lengthy report. More than a third of the 235 Democrats in the 435-member House have called for Trump's impeachment or the start of an impeachment inquiry, although House Speaker Nancy Pelosi has blocked an impeachment inquiry in favor of a range of investigations of Trump and his administration's policies.

Trump's Republican colleagues on the House investigating committees are predicting the Mueller testimony will amount to nothing more than a rehash of previously published information and also hope to emphasize what they see as the faulty reasoning behind why the investigation was even started.

Trump, in his tweets, attacked, as he has in the past, two Federal Bureau of Investigation agents involved in Mueller's investigation who exchanged private messages disparaging then-candidate Trump. The two agents, who were involved in a personal relationship, were removed from the probe.

House Judiciary Committee chairman Jerrold Nadler, one of the Democratic lawmakers overseeing Mueller's testimony, told Fox television over the weekend that he expects the prosecutor will give "very substantial evidence" that will make the case for impeaching Trump.

FILE - House Judiciary Committee Chairman Jerrold Nadler, a Democrat, speaks during a hearing on Capitol Hill in Washington, May 21, 2019.

"This is a president who has violated the law six ways from Sunday," Nadler said.

But Congressman Doug Collins, the top Republican on the Judiciary Committee, accused Democrats of "going after things that we've already known."

Nadler said Democratic lawmakers "have to present, or let Mueller present" the case against Trump, "because the administration must be held accountable and no president can be above the law."

Mueller has said he chose the words in his report very carefully and would not provide any other information in his public testimony.

But Nadler said Sunday he does not expect Mueller's appearance to be what he called a "dud."

"The president and the attorney general have lied to the American people about what was in the Mueller report...the president saying they found no collusion. That was not true, that it found no obstruction, that is not true."

Nadler says lawmakers will ask Mueller some very specific questions about parts of the report.

"Look at page 344, paragraph two...does that describe obstruction of justice...did you find that the president did that, for example," Nadler said.

FILE - Some redacted pages of Robert Mueller's report are seen on the witness table in the House Intelligence Committee hearing room on Capitol Hill, in Washington, April 18, 2019.

Republicans are upset at what they see as Democratic efforts to keep what they regard as a one-sided but already completed investigation of the president in the forefront of American news.

"It's like going back and finding a book on the shelf that looks new and then all of a sudden you begin to read and you find 'wait, I've already read this before'," Collins said on Fox television.

He said Republicans will also have questions for Mueller.

"Let me tell you, Republicans have not forgotten how and where the investigation started and there’s going to be a lot of questions for what he did say, what he didn’t say, and how this thing started," Collins said.