New Delhi, March 15 -- U.S. consumer sentiment plunged to a nearly 2-1/2-year low in March and inflation expectations soared amid worries that President Donald Trump's sweeping tariffs, which have ignited a trade war, would boost prices and undercut the economy.

The deterioration in sentiment and inflation expectations reported by the University of Michigan Surveys of Consumers on Friday was across political party affiliation, with consumers saying "frequent gyrations in economic policies make it very difficult for consumers to plan for the future."

That mirrors similar concerns in some business surveys. The uncertainty created by Trump's on- and off-again tariffs as well as an escalation in trade tensions risks derailing the economic e...