Japan should adopt measures aimed at attracting more of the almost $3 trillion managed by sovereign wealth funds, a trade ministry report said.

The nation must welcome state funds that "have no political purposes and invest for the long term," said a document to be released Wednesday by a trade ministry advisory panel, a copy of which was obtained by Bloomberg News. Any measures should conform to guidelines being drawn up by the International Monetary Fund, the report said.

Japan is seeking to rebound from the first drop in stock ownership by foreigners in five years, as investors, including the California Public Employees' Retirement System, question corporate governance in Asia's largest economy. Sony Corp. and Cosmo Oil Co. are among Japanese companies that received investments from sovereign funds in the past year.