U.S. President Barack Obama on Friday signed into law a measure restoring lower interest rates for student loans, pledging that the difficult political compromise leading to the legislation would be the first step in a broader battle to constrain the costs of university education. At a White House ceremony, Obama praised both Democrats and Republicans for finally agreeing on what he called a sensible approach to student loans. Friday's ceremony concluded lengthy negotiations that led to a rare bipartisan compromise to lower rates before school resumes in the autumn. About 11 million students this year are expected to have lower interest rates. The legislation links student-loan interest rates to the financial markets, offering lower rates this autumn because the government can borrow money cheaply at this time.