WASHINGTON—Treasury Secretary Janet Yellen urges other countries to support a global minimum tax rate for corporations, which is crucial for funding President Joe Biden’s infrastructure proposal, called the American Jobs Plan. The Biden administration proposes substantial tax increases on U.S. corporations to pay for the $2.3 trillion plan aimed at boosting investment in infrastructure, clean energy, manufacturing, housing, and other programs. Amid concerns that higher corporate tax rate would hurt the country’s market competitiveness, Yellen announced on April 5 that the United States is working with the Group of 20 (G20) countries to adopt a minimum global corporate income tax. Biden’s eight-year infrastructure plan will be fully paid for by tax increases on companies spread over 15 years. His proposal is to increase the federal corporate tax rate to 28 percent from 21 percent. Yellen said if an agreement among G20 economies is reached on the minimum corporate tax, it would end “a 30-year race …