An insurer shall not, except with the consent of the Commissioner, have at any time any combination of investments in or loans upon the security of the obligations, property, and securities of any one person, institution, or municipal corporation aggregating an amount exceeding 4 percent of the insurer's assets. This section shall not apply to investments in, or loans upon the security of general obligations of the Government of the United States or of any jurisdiction of the United States, nor to investments in foreign securities pursuant to subsection (a) of section 568 of this title nor include policy loans made pursuant to section 569 of this title.