Oil and gold prices have jumped, while shares have fallen.
A key member of the US central bank, Raphael Bostic, tells the BBC rates might only ease "at the end of 2024".
New official figures show that inflation, the rate at which prices rise over time, fell again in March.
The slowing jobs market has raised questions over when the Bank of England might cut interest rates.
Prices had already risen in expectation of action, with Brent crude near a six-month high last week.
Britain faces new challenges from an older and sicker population, according to a new report.
Under-investment had led to a "complicated and unwieldy system" being used, a review has found.
The economy grew by 0.1%, official figures show, with the production sector providing the biggest boost.
Inflation was 3.5% in March, a sign that cooling has stalled and interest rate cuts may be delayed.
Jamie Dimon, the boss of JPMorgan Chase, said the bank is preparing for both rate cuts and rises.
Employers added more than 300,000 jobs in March - the biggest gain in almost a year.