Wall Street slides after Powell's hawkish comments; Dow drops 235 pts

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Wall Street's main indexes fell on Monday as Federal Reserve Chair Jerome Powell's comments sparked bets of more aggressive interest rate hikes, adding to investor concerns as the Ukraine conflict rages on.

The U.S. central bank must move "expeditiously" to bring too-high inflation to heel, Powell said in his remarks prepared for delivery to a National Association of Business Economics conference, adding it could use bigger-than-usual interest rate hikes if needed.

Traders now see a 60.7% chance of a 50-basis point rate hike at the Fed's May meeting, up from about 52% before Powell's comments. The U.S. central bank last week raised