(CNBC) U.S. equities fell on Thursday, pulling back from record highs, on worries that a corporate tax cut could be delayed.

A proposed plan by Senate Republicans would push slashing the corporate tax rate from 35 percent to 20 percent until 2019. The move contrasts with a bill working its way through the House. The proposed Senate measure would also alter the individual tax system.

“That’s what gave us this new leg down,” said Art Cashin, director of floor operations at UBS, on CNBC’s “Squawk Alley.”

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