KYIV — While Congress heard closed-door testimony last week about President Donald Trump pushing Ukraine to investigate his opponents, Rudy Giuliani was holding his own private Ukraine meeting in his Manhattan office.

Giuliani, the Trump personal lawyer at the center of the firestorm as Trump faces likely impeachment, met with former Ukrainian diplomat Andriy Telizhenko, who alleges that Ukraine's government conspired with the Democratic National Committee to hurt Trump in 2016.

"We discussed what's happening in Ukraine, political updates, what the new (Ukrainian presidential) team is up to, what are the reforms going to be," Telizhenko said in an interview with NBC News. Giuliani has interviewed him for hours about his Ukraine allegations, although Telizhenko said their most recent meeting wasn’t focused on investigations. "We're friends now. He respects our country."

Far from keeping their heads down, those working in common cause with the president's and Giuliani's campaign to get Ukraine to investigate Trump's political opponents are moving ahead unabated, interviews in Kyiv and Washington with several of those involved reveal.

Their efforts come despite intense scrutiny from Congress, law enforcement and the media. Under oath, a parade of current and former U.S. officials have testified that Trump and his envoys leveraged a coveted White House meeting and military aid to Ukraine to pressure new President Volodymyr Zelenskiy to commit publicly to investigations into both the 2016 election and the Biden family.

In Ukraine, a group of parliamentarians are even working to stand up a new investigative commission — the Ukrainian analogue to a congressional select committee — to probe what they say was a Ukrainian government campaign to smear former Trump campaign chairman Paul Manafort in a bid to take down Trump in 2016. They also want to investigate the Bidens.

"Ukraine was involved in like the biggest scandal in recent U.S. political history, let alone Ukrainian. Definitely most of my colleagues here pretend it doesn't exist," said Oleg Voloshin, a lawmaker and Manafort associate, in an interview just outside the Rada, Ukraine's Parliament. "It started here, and it should finish here."

In Telizhenko's case, it's the continuation of a collaboration that started earlier this year when he said he saw Giuliani appear on Fox News alongside Victoria Toensing, a pro-Trump lawyer who State Department inspector general documents show worked with Giuliani on Ukraine.

He met with Giuliani in May and many times since — including in August, and September, and last Tuesday, at Giuliani's offices in New York. Giuliani didn't respond to requests for comment.

Igor Fruman exits federal court after an arraignment hearing in New York on Oct. 23, 2019. Stephanie Keith / Getty Images file

Telizhenko, a former Ukrainian diplomat and now a political consultant, has also worked for Ukrainian businessman Pavel Fuks, who was once a potential partner in Trump's unsuccessful bid to build a hotel in Moscow. He said he's continuing to push for investigations to protect himself and to clear his name, including from allegations that he's Russian intelligence.

"I'm not a Russian spy," Telizhenko said. "I'm doing this because I'm afraid for my security now, and I just want the story to be heard and questioned."

In fact, Telizhenko said he's refused offers of up to $10,000 from Russian media to give interviews about Ukrainian election-meddling.

He said he became "toxified" in Washington after a Politico article in January 2017 — a week before Trump's inauguration — first laid out the allegation that Ukrainian embassy officials in Washington had coordinated with a Democratic National Committee operative to dig up information linking Trump's campaign to Russia.

In the article, and in public comments since, Telizhenko has said his superiors at the embassy directed him to help the DNC consultant if he could. Two years later, after Toensing suggested he call Giuliani, the former New York mayor had him fly to New York the next day and interviewed him for five hours, Telizhenko said.

"Nobody else would listen," he said, noting that the FBI and State Department declined to interview him. "I am the witness of a robbery or a killing or whatever. You're questioning the guy who's allegedly the robber, and you're not questioning me as a witness?"

Indeed, Giuliani is still listening, even as investigations surrounding his work intensify.

Two of Giuliani's associates who helped seek damaging information about Trump's political opponents, the Soviet-born Florida businessmen Igor Parnas and Lev Fruman, have been indicted for allegedly funneling foreign money into U.S. elections to influence Ukraine relations. They pleaded not guilty. The New York Times reported that Giuliani himself is under criminal investigation for potential lobbying violations related to his Ukraine work.

Yet Giuliani, undeterred, alleged in a tweet last week that "frenzied" Democrats were trying to impeach Trump for acting within what he called Trump's constitutional powers to ask for "an investigation of serious crime committed in 2016 that did great damage to US and Ukraine."

"Dems covering up because it's bigger than you think," Giuliani added.

Although the effort by Voloshin and a handful of other parliamentarians to launch an investigative committee is unlikely to bear much fruit — it would require 150 lawmakers to vote for it — that may not matter politically if it allows Trump to say that Ukraine, too, is looking into 2016 meddling and the Bidens.

Even Zelinskiy, the target of Trump's pressure campaign, has said he's "ready to investigate interference in the election from the Ukrainian side, if it took place." During a marathon news conference last month aimed at dispensing with questions about Trump, he said the U.S. should hand over any evidence that would buttress an investigation.

Aiming to preserve his ability to work with Trump if he's re-elected, Zelenskiy has struggled to stay neutral even after the White House released a memo detailing his July 25 phone call with Trump that embarrassed the young Ukrainian leader, by showing him seeming eager to please the U.S. president.

In contrast, Valery Chaly, the former Ukrainian ambassador to the U.S., has said that giving in to "hotheads" who want a joint investigation into 2016 would be "suicide" for Ukraine.

Lev Parnas arrives at federal court for an arraignment hearing in New York on Oct. 23, 2019. Drew Angerer / Getty Images file

At the core of Trump's claim of Ukrainian meddling is the theory that Ukrainian officials tried to hurt him and help Democrat Hillary Clinton by exposing dirt in the heat of the 2016 election on Manafort, who was ultimately convicted of bank and tax fraud.

Chaly was Ukraine's envoy in Washington in 2016 when — Telizhenko, Giuliani and others allege — a part-time DNC contractor and Ukrainian-American named Alexandra Chalupa began looking into Manafort's ties to former Ukrainian President Victor Yanukovych, who fled to Russia during the "Euromaidan" revolution in 2014.

Although Chalupa acknowledges contact with the embassy during that period, she wrote on Facebook that it's "nonsense" to claim she was running a research operation or seeking Manafort dirt from the embassy. Ukraine's embassy denies working with her on anything election-related, and the DNC says she never did opposition research for the party.

Either way, there have been no indications that the top levels of Ukraine's government ordered or were aware of attempts to interfere in 2016. In contrast, U.S. intelligence agencies say Russia's extensive efforts to intervene in that same election were directed by the Kremlin.

Trump has continued to question whether Russia meddled in that race. He's repeatedly brought up — including in his call with Zelenskiy — the debunked conspiracy that a hacked DNC email server ended up in Ukraine to prevent FBI data forensics experts from determining the real hackers' identity.

Giuliani's involvement in Ukraine took form as special counsel Robert Mueller's investigation into Russian meddling and potential Trump campaign collusion was wrapping up. For Giuliani, Trump's personal lawyer, it was an opportunity to undermine any negative conclusions from the Mueller report by discrediting its origins.

He seized in particular on the "black ledger" — secret papers released publicly in 2016 showing $12.7 million in cash payments to Manafort from Yanukovych, Ukraine's pro-Russian former president. The revelation at the height of the 2016 campaign forced Manafort's resignation as Trump campaign manager.

Giuliani, Voloshin and others allege the black ledger was a forgery, even though Manafort acknowledged in his plea deal having raked in some $60 million in Ukraine.

As far back as 2016, Manafort was pushing the theory that Ukraine — not Russia — meddled in the election, according to documents from the Mueller investigation released just this weekend following a lawsuit from BuzzFeed.

There are competing theories for why a group of Ukrainian lawmakers would seek new investigations into alleged Ukrainian meddling just as Trump's efforts to secure those very investigations are driving a historic American political crisis.

Volodymyr Fesenko, who runs the Kyiv-based Penta Center for Political Studies, surmised that the lawmakers see an opportunity to get noticed in the U.S. and curry favor with the Trump administration. Others have pointed out that many of the lawmakers are among those within Ukraine's Parliament perceived to be friendlier to Russian interests.

Serhiy Leshchenko has another theory. The former parliamentarian and investigative journalist obtained and released many of the pages of the "black ledger" and has been relentlessly attacked by Giuliani since. House Democrats have subpoenaed any documents in the State Department's possession that mention his name.

Leshchenko and others argue the new effort in Parliament is a bid to help Dmytro Firtash, another Manafort associate and Ukrainian oligarch indicted on U.S. bribery charges whom the United States has been trying to extradite from Vienna for years. Firtash's business partner plays a major role in Voloshin's political party.

Dmytro Firtash in court in Vienna, Austria, on April 30, 2015. Ronald Zak / AP file

In his extradition fight, Firtash hired Toensing, the pro-Trump lawyer working with Giuliani, and her husband and legal partner Joe diGenova. NBC News has reported that Firtash is also linked to a natural gas deal that Fruman and Parnas, the businessmen who Giuliani says helped him find information on 2016 and the Bidens, were pitching in Ukraine. Toensing and diGenova have also said they hired Parnas as a translator on Firtash's case.

"They're part of this Firtash association," Leshchenko told NBC News in an interview in Kyiv. "These people decided to be helpful for Firtash, who is a part now of this narrative of Giuliani."

Firtash, too, helped Giuliani try to dig up dirt on Biden in a bid to get Giuliani's help in influencing the Trump administration to drop the extradition case, three people familiar with the matter told Bloomberg. That included an affidavit from a former Ukrainian prosecutor that Firtash used in court to argue his attempted extradition is politically motivated.

That affidavit made its way to Giuliani, who held it up during television interviews as evidence that Biden forced Ukraine to fire the prosecutor fired so Biden's son could avoid scrutiny for his own business dealings in Ukraine.

A "total lie," said Voloshin when asked whether his push for an investigation was related to Firtash. He insisted he'd never met Firtash and added, "I doubt he even knows of my existence."