WASHINGTON — A lawyer for the whistle-blower whose complaint set off an impeachment inquiry of President Trump said Sunday the same legal team is now representing a second whistle-blower, an intelligence official with firsthand knowledge of the president’s interactions with Ukraine.

The new whistle-blower “made a protected disclosure under the law and cannot be retaliated against,’’ Mark S. Zaid, one of the lawyers, said on Twitter.

Zaid confirmed a report by ABC News anchor George Stephanopoulos on his show, “This Week,’’ which said the new whistle-blower had already been interviewed by the intelligence community’s inspector general’s office but had not yet communicated with any congressional committees.

Another member of the legal team confirmed on Twitter the firm was now representing “multiple whistle-blowers’’ but declined to comment further.

It was not clear whether the new whistle-blower would file a formal complaint. Zaid said the second whistle-blower’s act of coming forward to the intelligence community inspector general had already secured whistle-blower protections.

The New York Times reported Friday that an intelligence official with more direct knowledge of Trump’s dealing with Ukraine than the first whistle-blower, and who had grown alarmed by the president’s behavior, was contemplated coming forward. The second official was among those interviewed by the inspector general to corroborate the allegations of the original whistle-blower, one of the people briefed on the matter said.

The new whistle-blower matches the description of the official that the Times reported on last week. Zaid said he did not know whether the individual was the same person.

The first whistle-blower, a CIA officer who was detailed to the National Security Council, filed a complaint in August outlining how Trump used his power to push Ukraine to investigate his political rivals.

Trump has tried to undermine the credibility of the first whistle-blower, whose identity is not publicly known, by saying that the individual was trading on secondhand information.

The White House did not respond to a request for comment. But Trump preemptively went on the attack Saturday night. “The first so-called second hand information ‘Whistleblower’ got my phone conversation almost completely wrong, so now word is they are going to the bench and another ‘Whistleblower’ is coming in from the Deep State, also with second hand info,’’ Trump wrote on Twitter on Saturday night, referring to his now-infamous July 25 phone call with President Volodymyr Zelensky of Ukraine, in which he leaned on Zelensky to investigate Joe Biden, the former vice president and current presidential candidate, as well as his son Hunter. “Keep them coming!’’

Trump’s personal lawyer, Rudy Giuliani, framed the news of the new whistle-blower on Sunday as a political hit on the president. “SURPRISE Democrat lawyer has other secret sources,’’ Giuliani wrote on Twitter. He added that the bottom line was that there was “no quid pro quo’’ attached to Trump’s pressure on Ukrainian officials to investigate his political rivals and called the story an “ORCHESTRATED DEM CAMPAIGN LIKE KAVANAUGH,’’ referring to the sexual misconduct allegations against Justice Brett Kavanaugh during his Supreme Court confirmation hearing.

Zaid works for Compass Rose Legal Group, a law firm that specializes in representing whistle-blowers. The team also includes Andrew P. Bakaj, the lead lawyer, and I. Charles McCullough III. “I can confirm that my firm and my team represent multiple whistleblowers in connection to the underlying August 12, 2019, disclosure to the Intelligence Community Inspector General,’’ Bakaj said on Twitter. “No further comment at this time.’’

Democrats who are building the impeachment case against Trump sought to paint the accumulation of evidence against him as inevitable Sunday. Meanwhile, the White House had few allies on the Sunday show circuit who strongly defended the president’s actions.

Representative Jim Himes of Connecticut, the second-ranking Democrat on the House Intelligence Committee, said his panel had not yet heard from a second whistle-blower as of Sunday morning. But he hastened to argue that the speed with which details were becoming public was itself a strong sign of wrongdoing.

“We’re sort of sitting here watching the information flow out of the White House, damning information, facts that are undisputed,’’ Himes said on CBS’s “Face the Nation.’’ “What’s happening is that people around the president, professionals, who are in the Oval Office, who are in the Situation Room, are watching what is happening and are finally saying, ‘my God, this cannot happen anymore,’ and they are coming forward.’’

The intelligence panel is still working with the first whistle-blower and the director of national intelligence to arrange a private interview. The White House, which has been riven internally about how to handle impeachment proceedings, with no one clearly in charge, did not have any senior officials making the case to defend Trump on Sunday.

And those congressional allies who did make public comments Sunday either focused on attacking Democrats’ handling of the case or said they would reserve judgment until they saw more facts.

Senator Roy Blunt, Republican of Missouri and a key member of the Senate Intelligence Committee, said he was interested to learn more about the new whistle-blower and offered no defense of Trump’s actions toward Ukraine. Instead, he said he first wanted to see the results of the Senate’s bipartisan investigation of the matter before making a judgment.

“You have to assume if it is essentially a partisan vote in the House, that that sets the stage for likely the same kind of vote in the Senate,’’ Blunt said on CBS. “But let’s see what the facts are.’’

Others were more squarely behind the president.

On ABC’s “This Week,’’ Representative Jim Jordan of Ohio, one of Trump’s most steadfast defenders, said that the president was merely interested in rooting out legitimate accusations of corruption and that Democrats were unfairly vilifying him for it.

But pressed a half-dozen times to say whether he approved of Trump’s public remarks this past week calling on China to investigate the Bidens, Jordan would not answer.

“I think he has you guys all spun up,’’ he said, repeating a line frequently used by Republicans in recent days. “I don’t think he really meant go investigate. Do you think China is really going to investigate?’’

Senator Ron Johnson, Republican of Wisconsin, said in a heated exchange on “Meet the Press’’ that Trump had “vehemently, angrily denied’’ to him withholding aid for Ukraine in exchange for investigating his political rivals.

“Unlike the narrative of the press that President Trump wants to dig up dirt on his 2020 opponent, what he wants is an accounting of what happened in 2016,’’ Johnson said.

Republican Senator Lindsey Graham of South Carolina, one of Trump’s most vocal backers, provided perhaps the strongest defense of the president. He said that there was nothing wrong with Trump’s July conversation with the Ukrainian president and that the accusation look like a ‘‘political setup.’’

As for Trump, he tweeted and retweeted, with the Bidens a main target. ‘‘The great Scam is being revealed!’’ he wrote at one point, continuing to paint himself as the victim of a ‘‘deep state’’ and hostile Democrats.

As the president often does when he feels under attack, he trumpeted his strong support among Republican voters. He kept lashing out at Utah Senator Mitt Romney, one of the few Republicans who has publicly questioned Trump’s conduct.

‘‘The Democrats are lucky that they don’t have any Mitt Romney types,’’ Trump wrote, painting the 2012 GOP presidential nominee as a traitor to his party. Romney had tweeted that Trump’s ‘‘brazen and unprecedented appeal to China and to Ukraine’’ for an investigation of Biden is ‘‘appalling.’’

Material from the Associated Press was used in this report.