US regulators failed to put the finishing touches on a much-debated, long-delayed rule to limit speculation in commodities like oil and gold, opting instead to propose a scaled-back version and leave its outcome in the hands of the Trump administration.

The Commodity Futures Trading Commission voted unanimously Monday to float, for the third time since 2011, a proposed rule that would cap the size of trading positions firms could take in more than two dozen core commodity contracts, including a variety of energy and precious metals commodities, to curb any one trader's influence.