WASHINGTON — The Trump administration is proposing rules for investors in a new program that it says could have a big impact on economically depressed areas around the country. About 8,700 so-called “opportunity zones” have been set up in all 50 states to lure investors and developers with tax breaks.

The rules from the Treasury Department, issued Friday, lay out the period of time that individuals or companies must hold on to their investments in the zones to avoid paying taxes on resulting profits.

Administration officials say the goal of the program is to create businesses and jobs in low-income areas and lift residents out of poverty. Treasury Secretary Steven Mnuchin predicts that $100 billion in private capital will be invested in the new zones.

“This incentive will foster economic revitalization and promote sustainable economic growth,” Mnuchin said in a statement.

But some critics say the new rules and the way the program is set up will benefit real estate developers, and will pull investment toward more well-off areas that need it least.

Timothy Weaver, a professor at the State University of New York in Albany who has studied similar development programs, said the program “doesn’t have much of an effect other than giving tax breaks to people who are going to invest anyway.”