WASHINGTON — President Obama asked Congress on Wednesday to scrub the corporate tax code of dozens of loopholes and subsidies to reduce the top rate to 28 percent, from 35 percent, while giving preferences to manufacturers that would set their maximum effective rate at 25 percent.

 

Mr. Obama’s proposal, being outlined by Treasury Secretary Timothy F. Geithner at a midday briefing, also would establish a minimum tax on multinational corporations’ foreign earnings, to discourage “accounting games to shift profits abroad” or actual relocation of production overseas, a senior official said before the briefing.

With this framework for changes, Mr. Obama will enter an election-year debate with Republicans in Congress and in the presidential race who seek even lower taxes for businesses, as well as lower individual tax rates than Mr. Obama has embraced.