Fox News reported Biden leading Trump by 10 points in poll -- the same day of the Ukraine call
President Donald J. Trump arrives at the Memorial Amphitheater during the 149th annual Department of Defense (DoD) National Memorial Day Observance. (DoD Photo by U.S. Army Sgt. James K. McCann)

President Donald Trump's phone call with Ukraine's president came the same day Fox News reported Joe Biden ahead by 10 points in a head-to-head matchup.

The president complained bitterly about the report the next morning on Twitter, but the conservative network reported the results of its own poll on July 25 -- which has been revealed as the day Trump alarmed his national security staff by asking Ukraine to investigate Biden for alleged corruption.

"@FoxNews is at it again," Trump griped on July 26. "So different from what they used to be during the 2016 Primaries, & before - Proud Warriors! Now new Fox Polls, which have always been terrible to me (they had me losing BIG to Crooked Hillary), have me down to Sleepy Joe."

"Even considering the fact that I have gone through a three year vicious Witch Hunt," he continued, "perpetrated by the Lamestream Media in Collusion with Crooked and the Democrat Party, there can be NO WAY, with the greatest Economy in U.S. history, that I can be losing to the Sleepy One. KEEP AMERICA GREAT!"

It's not clear whether Trump would have been aware of the poll results at the time of his call, which the whistleblower complaint places in the "early morning" of July 25.

"Fox & Friends," which the president watches regularly, doesn't appear to have discussed the Fox News poll, based on a search of transcripts from that day, but Biden's campaign teased Trump about the results in a tweet posted at 10:35 a.m.

“@realDonaldTrump, we know you love the polls," the campaign tweeted. "We’re glad you saw the latest from Fox: Biden 49%, Trump 39. You’re losing by ten. Have a nice day.”

That call with Ukrainian president Volodymyr Zelensky eventually resulted in a whistleblower complaint that finally prompted House Speaker Nancy Pelosi (D-CA) to launch a formal impeachment inquiry.