President Bush has named Republican Congressman Christopher Cox as the new head of the Securities and Exchange Commission.

The California Congressman replaces William Donaldson, who resigned Wednesday.

President Bush says Mr. Cox will be an outstanding leader of the SEC who will guard the integrity of the stock market.

Congressman Cox has been in the House of Representatives since 1988 and takes over the SEC at a time when business groups are pressuring the agency to scale back regulations.

The 52-year-old Congressman is chair of the House Committee on Homeland Security and has backed tax cuts.

He is also the author of the Securities Litigation Reform Act, a law making it more difficult for investors to sue for misconduct. His bill was the only measure to become law over former President Bill Clinton's veto.

Mr. Donaldson leaves his post at the end of June.