How can he do it?

Drudge is headlining an article that points out the Egypt is selling a billion dollars worth of bonds with a guarantee by the USA. This guarantee reduces the interest costs for Egypt, and that may be a good thing. My question, however, is how can the US guarantee debt if it is already at the legal debt limit? Surely it is not appropriate for the US to indirectly take out a loan through the guarantee when it could not do so directly. Someone needs to explain this.