(Adds detail on testimony, hearing)

WASHINGTON, July 10 (Reuters) - U.S. Treasury Secretary Timothy Geithner is expected to propose on Friday giving securities and futures regulators authority to police the largely unregulated over-the-counter derivatives market, according to a document obtained by Reuters.

"Our plan will help prevent market manipulation, fraud and other abuses by providing full information to regulators about activity in the OTC derivative markets," Geithner said in the testimony to be delivered to Congress.

The $450 trillion privately-traded global derivatives market includes credit default swaps, the financial instrument that nearly toppled insurer American International Group (AIG.N: Quote, Profile, Research).

Later on Friday, Geithner is due to testify before two key Congressional committees on the government's plan to regulate derivatives.

According to the document, all major dealers such as JPMorgan Chase (JPM.N: Quote, Profile, Research) and Goldman Sachs (GS.N: Quote, Profile, Research) would be subject to "substantial supervision and regulations," including conservative capital requirements and strong business conduct standards.

The Securities and Exchange Commission, which oversees securities, and the Commodity Futures Trading Commission, which supervises futures markets, would have authority to impose recordkeeping and reporting requirements on the derivatives.

The SEC and the CFTC would also have clear authority for civil enforcement and regulation of fraud, market manipulation and other abuses, the document said.

The Obama administration has already proposed sweeping reforms for the country's financial regulation including broad proposals to regulate derivatives.