A transcript of the July 25 phone call between President Donald Trump and Ukraine's president was not shared electronically among officials because the contents were considered so alarming, The New York Times reported Thursday.

Instead, officials were ordered to use only printed hard copies, given to a "select group," The Times reported, citing multiple anonymous officials.

The details add to the sense of extreme secrecy around the call, following a whistleblower complaint alleging that officials tried to "lock down" the transcript because of the political fallout it could cause.

Trump on Wednesday released a memo summarizing the call — but not a full transcript. The memo showed Trump asking Ukrainian President Volodymyr Zelensky to investigate Trump's Democratic rival Joe Biden and his son Hunter Biden.

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White House officials were said to be so alarmed by President Donald Trump's July 25 call with his counterpart in Ukraine that transcripts were allowed to be circulated only in paper form.

Officials who heard the call, in which Trump asked Ukrainian President Volodymyr Zelensky to investigate former Vice President Joe Biden, took "extraordinary efforts" to stop too many people from learning about it, The New York Times' Peter Baker reported Thursday.

Officials told The Times that an order had been given not to distribute the transcript of the call electronically.

Printed copies were instead delivered by hand "to a select group," The Times said. It did not say who gave the order.

Trump during a bilateral meeting with Ukrainian President Volodymyr Zelensky on the sidelines of the 74th session of the United Nations General Assembly in New York City on Wednesday. Jonathan Ernst/Reuters

The content of the call caught the White House off-guard, according to The Times. The paper said officials had not limited how many people could listen to the call, which aides apparently expected to be unremarkable.

These details add to the allegations in an explosive whistleblower complaint, made public Thursday morning, involving the call as well as broader dealings with Ukraine from Trump's allies.

Read more: Read the full declassified whistleblower complaint about a phone call between Trump and Ukraine's president

The complaint was lodged in August by an anonymous intelligence official to the inspector general for the intelligence community. It said that White House officials were "deeply disturbed" by the phone call and that officials feared they had seen Trump "abuse his office for personal gain."

The whistleblower alleged that officials tried to "lock down" all records of the call, especially the transcript.

He or she said officials were directed by White House lawyers to remove the electronic transcript from its usual place in the computer system and move it to an area reserved for sensitive, classified information.

The acting director of national intelligence, Joseph Maguire, being sworn in before testifying before the House Intelligence Committee on Thursday. Associated Press

The whistleblower said it was "not the first time" that a transcript of a Trump conversation had been put into this system.

Read more: The White House has a complete transcript of Ukraine call but hid it in a possible abuse of power, whistleblower complaint says

Some officials worried that the transfer of records "would be an abuse of the system," the whistleblower said.

Some details of the complaint were corroborated by a memo about the phone call released by the White House on Wednesday. The memo was not a full, verbatim transcript of the call, but was instead made from staff notes.

According to the White House memo, Trump said during the call: "I would like you to do us a favor." He asked that Zelensky work with Trump's personal lawyer, Rudy Giuliani, and Attorney General William Barr in looking at Joe Biden and his son Hunter Biden.

Zelensky and Trump meeting Wednesday in New York. Volodymyr Zelensky

The Washington Post reported Wednesday that some senior officials, including Secretary of State Mike Pompeo, were hesitant to release the memo.

Read more: Trump aides quickly regretted publishing the Ukraine call that has intensified calls for his impeachment, report says

The Times report, published late Thursday, also demonstrates how officials are revealing information about the call since the complaint was made public. The memo is largely based on testimony from such officials.

Republicans are arguing that Trump's call does not explicitly show a quid pro quo exchange and that the complaint was based on secondhand information — but the acting director of national intelligence, Joseph Maguire, said on Thursday that much of the complaint's content was confirmed in the White House's own memo.