Image copyright Getty ImagesStudents in England, Wales and Northern Ireland will face interest rates on their loans of up to 6.3%, following an increase in the Retail Prices Index (RPI) measure of inflation. The rise from 6.1% currently will take effect from September for students and graduates under the 2012 fee scheme. The increase comes as the government is conducting a review of post-18 education and funding. Ministers say the role of interest rates will be considered in the review. The RPI inflation rate in March is used to set the interest on student loans from the following September. Those starting or continuing at university this autumn will be charged interest of 6.3% - RPI at 3.3% plus 3% - from when they start studying, until the April after they graduate. From that point, the loan becomes payable above a certain income threshold - which the government announced earlier this month is to be raised from £21,000 to £25,000. For graduates, the interest is on a sliding sc..