Uncle Sam’s biggest creditor faces a fiscal crisis ‘worse than Greece’ as its borrowing costs hit 20-year high 

• Japan's prime minister warned members of parliament the country cannot afford any tax cuts funded through the issue of new debt as calls grow for stimulus ahead of July elections to the upper house. The country holds $1.13 trillion in U.S. Treasury debt, even as its own debt-to-GDP ratio runs at roughly 250%.

Japan, the single largest foreign financier of the U.S. federal government, faces its own mountain of debt just as its economy is beginning to shrink.

Prime Minister Shigeru Ishiba...