The Federal Reserve may curtail Wall Street commodity businesses after lawmakers said banks' role in energy, power, and metals markets spurred unfair trading advantages and could threaten financial stability.

At a Senate hearing today, Fed Governor Daniel Tarullo said curbs under consideration include ownership limits, restricting how much revenue can be derived from commodities, and requiring Wall Street firms to boost capital. He said the new rules, to be proposed early next year, could restrict banks from investing in oil tankers, coal mines, and other businesses involved in physical commodities.

"We are focusing on the risk to safety and soundness presented by specific activities and on whether those risks can be appropriately and adequately mitigated," Tarullo said at the hearing held by the Senate Permanent Subcommittee on Investigations.