Lobbyists representing then-Ukrainian President-elect Volodymyr Zelensky's campaign met or corresponded with 10 Trump administration officials in the days surrounding Zelensky’s April election, according to foreign-agent filings with the Department of Justice.

Those contacts, which occurred throughout April, coincided with an effort by President Trump and his personal attorney Rudy Giuliani to press for additional scrutiny of former Vice President Joe Biden’s son’s business dealings in Ukraine, efforts that are now at the center of an impeachment inquiry into the president.

The Foreign Agents Registration Act filing shows extensive efforts by the new Ukrainian president’s team to open up channels of communication with the Trump administration and arrange an official delegation to Kyiv. According to an intelligence-community whistleblower, Trump was reluctant to permit high-level engagement with Zelensky before the Ukrainian president acceded to requests for a new investigation into Biden’s youngest son, Hunter, who formerly sat on the board of a large Ukrainian energy company.

In the weeks between a Ukrainian election that winnowed the presidential field to two and the subsequent runoff that saw Zelensky unseat the incumbent president, his campaign hired Signal Group Consulting to advance its interests in Washington, FARA filings show.

Signal Group was paid $60,000 plus expenses for its work, which lasted only about six weeks, from early April to May 21, the day after Zelensky was inaugurated. The firm initially declined to go into much detail about its meetings on Zelensky’s behalf, referring The Daily Beast’s questions last week to a DOJ filing that listed the offices and agencies the firm contacted on Zelensky’s behalf, but not the individual staffers with which the firm worked.

But the Signal Group recently amended that filing to provide significantly more detail. Among its contacts in the Trump administration, the firm told DOJ, were Alexander Vindman, who oversees Eurasia for the White House National Security Council and joined Energy Secretary Rick Perry on a small Trump administration delegation to Zelensky’s inauguration in May.

That delegation merited a mention in an intelligence-community whistleblower complaint released last week alleging that Trump and Giuliani pressured Ukrainian leaders, including Zelensky, to investigate potential Democratic presidential challenger Joe Biden’s son’s business dealings in Ukraine. The scandal is now at the center of an impeachment inquiry against the president.

The Signal Group’s lobbying campaign took place right as Trump and Giuliani began to turn up the public pressure on Ukraine to look into the Biden situation. Those efforts culminated in a phone call in late July between Trump and Zelensky, during which the former pledged the assistance of Giuliani and Attorney General Bill Barr in digging into corruption allegations against the former vice president and his family.

The public has not yet seen a transcript of Trump’s first call with Zelensky, which took place on April 21, making it difficult to know whether he exerted comparable pressure on the new Ukrainian leader at the time. But Giuliani was already deeply involved in attempting to unearth alleged Biden malfeasance in the country.

There’s no indication that the Signal Group’s work was related to that campaign. But for a time, the firm made a number of high-level connections between Zelensky’s team and key members of the Trump administration as well as several members of Congress, media organizations, and think tanks.

According to its DOJ filing, Signal Group representatives also met John Erath, the NSC’s deputy director for European affairs, and State Department officials including Deputy Assistant Secretary George Kent and Brad Freden, the director of the office of Eastern European affairs.

In an email last week, John Procter, Signal Group’s managing director, declined to go into specifics about its work. “Signal Group’s work for Mr. Zelensky and the Servant of the People party through Marcus Cohen concluded on May 21 and is detailed in our FARA filings with the Department of Justice,” Procter said. “I would direct you to the details of those documents for your reporting. The firm does not have anything additional to add.”

According to its DOJ filing, the Signal Group is a wholly owned subsidiary of the prominent Washington law and lobbying firm Wiley Rein. That firm previously represented Yulia Tymoshenko, a former Ukrainian prime minister who also ran for president this year.

Its Zelensky contract was arranged through an intermediary named Marcus Cohen, whom The Daily Beast was not able to reach. Cohen previously told Radio Free Europe/Radio Liberty that he arranged for the lobbying contract independently of Zelensky, who has denied any knowledge of a U.S. lobbying campaign on his behalf.

But Cohen signed the Signal Group’s DOJ filings “on behalf of the Zelensky Campaign,” and according to RFE/RL, both Cohen and Ivan Bakanov, Zelensky’s campaign chairman, attended meetings with Signal Group lobbying targets during its springtime influence campaign.

Both men were spotted among a dozen attendees at one particularly conspicuous meeting in mid-April: They and a group of unidentified compatriots went out for dinner at the steakhouse in the lobby of the Trump International Hotel just down the street from the White House.