No respite in sell-off of low-risk bonds

By Nigel Stephenson LONDON (Reuters) - Low-risk bonds sold off again on Tuesday driving down stocks and helping push the euro higher against the dollar. Ten-year U.S. Treasury yields , the benchmark for global borrowing costs, hit their highest since early December, while German 10-year yields added 8 basis points to 0.67 percent. Volatility in the bond markets weighed on stocks, adding to existing investor anxiety over the perilous state of Greece's finances. Shares in Europe and followed