The federal government agreed to pay $16 million of the $30 million that the District of Columbia expects to spend on security for next month's World Bank and International Monetary Fund meetings.
The money will help pay for out-of-town police officers and the protective gear and medical supplies they may need.
The district will pay $12.6 million for overtime for its own police officers, firefighters, emergency service workers and the public works crews that will have to clean up after the meetings.
Police say there could be more than 100,000 protesters in the nation's capital for the Sept. 29-30 meetings. Protests in Genoa, Italy, last month turned violent during a summit of the world's industrial powers.