House Intelligence Committee Chairman Adam Schiff (D-CA) speaks during a House Intelligence Committee hearing featuring the testimony of Marie Yovanovitch, former U.S. ambassador to Ukraine, as part of the impeachment inquiry into President Donald Trump on Capitol Hill in Washington, November 15, 2019.

WASHINGTON — House Intelligence Committee Chairman Adam Schiff said Sunday that the two weeks of public hearings produced "overwhelming evidence" that President Donald Trump conditioned official acts for favors from Ukraine that would benefit his re-election bid, arguing that it's "urgent" for the House to move forward with its impeachment inquiry.

In an interview on "Meet the Press," the California Democrat overseeing the hearings said that while his committee has no more public testimony scheduled, he doesn't "foreclose the possibility of others" being added.

Still, Schiff said he felt confident that the five days of open hearings with 12 witnesses produced clear evidence against the president even without hearing from some central Trump administration officials. And he said that he didn't want to delay the House's progress with protracted legal battles aimed at compelling those officials, like National Security Adviser John Bolton and Chief of Staff Mick Mulvaney, to testify.

"We've already accumulated quite overwhelming evidence that the president, once again, sought foreign interference in an election — conditioned official acts of a White House meeting that Ukraine desperately wanted as well as $400 million of bipartisan tax-payer funding — to get these political investigations that he thought would help his reelection," Schiff said.

"We view this as urgent, we have another election where the president is threatening more foreign interference. But at the same time, there are still other witnesses, other documents that we'd like to obtain. But we are not willing to go the months and months and months of rope-a-dope in the courts, which the administration would love to do."

Schiff's committee heard from a lengthy list of officials over the two weeks, including the Ambassador to the European Union, Gordon Sondland, who testified that there was a quid-pro-quo between the scheduling of a White House meeting with the Ukranian president and an ask for the country to investigate former Vice President Biden and his son.

The committee also heard from various diplomats and White House officials who shared their concerns with the president's conduct, particularly on the July phone call with the Ukrainian president that prompted a whistleblower complaint that sparked the inquiry.

Schiff told "Meet the Press" that while he initially had a "deep interest" in hearing from that CIA whistleblower, that he felt that Trump and his allies effectively put the life of that whistleblower "in danger." President Trump reportedly claimed that the whistleblower was "close to a spy" during private remarks in September.

"We don't need the whistleblower's second-hand evidence anymore," Schiff said, arguing that the committee had already heard from witnesses at the center of the issues in question.

"It would only serve to endanger this person and to gratify the president's desire for retribution."

If the House files articles of impeachment and passes them with a vote, it's up to the Senate to hold a trial to see if Trump will be removed from office.

While some Republicans have floated calling Schiff as a witness in an attempt to challenge his conduct as chairman, he told "Meet the Press" that if the Republicans call him to testify, "then they pretty much made a decision not to take this process seriously."

But Mississippi Republican Sen. Roger Wicker, who would serve as one of the jurors in a Senate impeachment trial, disagreed with Schiff's optimism about the Democrats' impeachment case.

He argued that "Democrats had a bad week last week," pointing to recent polls showing public support for impeachment dropping.

He criticized Schiff for not calling the whistleblower to testify because Republicans might want to "cross-examine" that person to stress-test their case.

And overall, he said the Democrats didn't produce enough evidence to warrant Congress removing a president from office.

"If you're going to try to remove the president of the United States from office, you need concrete evidence. And the other person on the part of this so-called quid-pro-quo denies that there was a quid-pro-quo," Wicker said of Ukrainian President Volodymyr Zelenskiy.

"There was no direct evidence of pressure on the Ukrainian government to do a certain act in order for the aid to go forward."