Benchmark 10-year Treasury notes rose 10/32 in price to push their yield down to 1.6973%.
"The transcript of his call released yesterday did not seem to have anything specific that Trump said, 'do this for that,'" Lederer said.
"The whistleblower complaint looks like there was more to it, but I don't know. Overall, it's just the idea that markets don't like uncertainty," he added.
MSCI's gauge of stocks across the globe shed 0.06%, while the pan-European STOXX 600 index of large, mid- and small companies rose 0.61%.
On Wall Street, the Dow Jones Industrial Average fell 79.59 points, or 0.3%, to 26,891.12. The S&P 500 lost 7.25 points, or 0.24%, to 2,977.62 and the Nasdaq Composite dropped 46.72 points, or 0.58%, to 8,030.66.
Facebook Inc slipped 1.47% as a person familiar with the matter told Reuters that the U.S. Justice Department will open an antitrust investigation of the social media company.
The dollar rose to a three-week high against a basket of currencies, helped by continued tightness in U.S. money markets, while heightened political tensions and a relatively dismal economic outlook weighed on the euro and sterling.
Increased political tensions on both sides of the Atlantic - the unfolding effort by U.S. congressional Democrats to impeach Trump and ongoing uncertainty regarding Britain's exit from the European Union - was likely to keep the greenback in demand, analysts said.
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The dollar index rose 0.16%, with the euro down 0.2% to $1.0919. The Japanese yen weakened 0.06% versus the greenback at 107.86 per dollar.
Crude oil prices pared losses late in the session after the U.S. Department of Defense said it would deploy radar systems, Patriot missiles and about 200 personnel to bolster Saudi Arabia's defenses after an attack on the kingdom's oil installations earlier this month.
Brent crude futures settled up 35 cents at $62.74 a barrel, while U.S. West Texas Intermediate (WTI) crude futures fell 8 cents to settle at $56.41 a barrel.
U.S. gold futures settled up 0.2% at $1,515.20.
(Reporting by Herbert Lash, additional reporting by Gertrude Chavez-Dreyfuss in New York; Editing by Nick Zieminski and Dan Grebler)
