The sell-off in Treasuries led to a surge in 30-year yields on Wednesday, which is expected to be the biggest one-day rise since early January.

Medium-and long-term Treasury yields are higher, while long-term yields are rising even more, steepening the curve. At one point, the yield on the 30-year note rose about 11 basis points, hitting an one-year high of 2.29 per cent. The yield on the 10-year note rose as much as 9 basis points to 1.43 per cent.

Global bond markets have been hit hard this year by US stimulus and the prospect of reflation, with volatility indicators rising to multi-month highs. This has raised concerns about possible volatility in safe-haven assets such as US Treasuries and German bunds. Although Federal Reserve Chairman Jerome Powell called the recent rise in bond yields a "declaration of confidence" about the economic outlook, it still put pressure on central banks to keep financial conditions loose.

"the market is nervous about more stimulus measures, worried about the risk of rising inflation and worried about quantitative easing," said Gennadiy Goldberg, senior U.S. interest rate strategist at TD Securities. "Convex arbitrage and position stops may have exacerbated the sell-off."