The International Finance Corp (IFC), the World Bank's lender to the private sector, has started work on a return to the market for Islamic bonds, with plans to issue sharia-compliant debt after summer in the Gulf region. Details such as currency, tenor and size were not yet available. The IFC, which aims to spur private investment in developing countries, last sold a $100 million five-year sukuk in 2009, listing it on the Dubai and Bahrain bourses. Its first sukuk came in 2004 in Malaysia, a 500 million Malaysian ringgit ($134 million) three-year deal. In December, the International Finance Facility for Immunisation Co (IFFIm), for which the World Bank acts as treasury manager, issued a $500 million debut sukuk.