Get breaking news alerts and special reports. The news and stories that matter, delivered weekday mornings.

House Judiciary Committee Chairman Jerry Nadler said Sunday that his committee will request documents from more than 60 people connected to President Donald Trump and his administration "to begin investigations to present the case to the American people about obstruction of justice, corruption and abuse of power."

Nadler, D-N.Y., said on ABC's "This Week" that those receiving document requests will include the president's son, Donald Trump Jr., and Trump Organization Chief Financial Officer Allen Weisselberg, who was named by Trump's former longtime attorney Michael Cohen at his public testimony before the House Committee on Oversight and Government Reform last week in a discussion of alleged campaign finance violations and other alleged financial irregularities. Weisselberg will soon be called by the House Intelligence Committee to testify.

Nadler said Cohen's testimony "directly implicated the president in — in various crimes, both while seeking the office of president and while in the White House," calling the campaign-finance violations Cohen pleaded guilty to in August as a result of hush payments he made to silence women who allege having had affairs with Trump prior to the 2016 election "the major one." Any attempt to "sabotage a fair election would be an impeachable offense," he added.

"Impeachment is a long way down the road," Nadler said. "We don’t have the facts yet, but we’re going to initiate proper investigations." He added that it's Congress' "job to protect the rule of law."

Let our news meet your inbox. The news and stories that matters, delivered weekday mornings. This site is protected by recaptcha

"That’s our core function," he said. "And to do that we are going to initiate investigations into abuses of power ... into corruption and into obstruction of justice."

Weisselberg was granted limited immunity by New York prosecutors to provide information in their case involving hush money Cohen paid to women. Weisselberg does not have an ongoing cooperation agreement with prosecutors, multiple sources have told NBC News.

Nadler said he believes that president has obstructed justice with regard to special counsel Robert Mueller's investigation.

"It’s very clear that the president obstructed justice," Nadler said. "It’s very clear — 1,100 times he referred to the Mueller investigation as a witch hunt, he tried to — he fired — he tried to protect Flynn from being investigated by the FBI. He fired Comey in order to stop the Russian thing, as he told NBC News."

Trump again referred to the probes stemming from Russian meddling in the 2016 election as a "witch hunt" on Sunday morning.

"I am an innocent man being persecuted by some very bad, conflicted & corrupt people in a Witch Hunt that is illegal & should never have been allowed to start - And only because I won the Election!" Trump tweeted Sunday morning. "Despite this, great success!"

Nadler said Sunday that his committee does not yet "have the evidence all sorted out and everything" to "do an impeachment."

Impeachment proceedings, if they were to take place, would begin in Nadler's committee.

"Before you impeach somebody, you have to persuade the American public that it ought to happen," he said. "You have to persuade enough of the — of the opposition party voters, Trump voters."

"This Week" host George Stephanopoulos pointed out that is "a very high bar."

"Yeah. It is a very high bar," Nadler said. "The United States trying to steal the last — to reverse the results of the last election. We may or may not get there. But what we have to do is protect the rule of law."