President Barack Obama is nominating a top Treasury Department official to run the independent agency that regulates the futures and options market.

The White House says Obama will announce the nomination of Timothy Massad to head the Commodity Futures Trading Commission on Tuesday. For the past three years, Massad has overseen the Troubled Asset Relief Program, the bank rescue plan known as TARP.

Obama is expected to use Massad's nominating ceremony to call on Congress to fully fund the CFTC, one of the smallest and most thinly funded U.S. agencies. Obama's 2010 financial overhaul law gave the agency the task of laying down rules for oversight of derivatives, the complex instruments traded in a $700 trillion worldwide market that has been unregulated.

The agency has now completed 43 of the 60 rules it was charged with putting into motion under the overhaul law. That compares with 35 final rules out of 95 for the Securities and Exchange Commission and a total 43 final rules of 135 for the federal bank regulators: the Federal Reserve, the Federal Deposit Insurance Corp. and the Office of the Comptroller of the Currency.

For the CFTC, some of the thorniest and most critical rules are among those that remain. They include the so-called Volcker Rule, which would prohibit banks from trading for their own profit. Its latest version includes an exemption for banks to make such trades when they are used to offset other risks taken. Adoption of the rule has been delayed largely because of Wall Street banks' objections and the need to get a handful of federal agencies, including the CFTC, to agree on its final form.

If confirmed by the Senate, Massad would succeed Gary Gensler, whose term ends in January.

Under Gensler, the CFTC wrote new rules to bring derivatives under government supervision for the first time. The complex investments, traded in a secretive, $700 trillion global market, were blamed as the accelerant on the fire that ignited the 2008 financial crisis.

The value of derivatives is based on a commodity or security, such as oil, interest rates or currencies. They are often used to protect businesses that produce or use the commodities, such as farmers or airlines, against future price fluctuations. But they also are used by financial firms to make speculative bets.