US Treasuries gained, while Wall Street and the greenback fell, amid concern that the political firestorm surrounding President Donald Trump means he won't be able to deliver on his plans for tax and regulation cuts.
Investors are concerned about reports of a leaked memo by former FBI director James Comey, which suggests Trump tried to obstruct a federal investigation, the most serious in a series of controversies.
"I think the biggest issue right now is what does this mean for the plan that we thought we were on,"Jeremy Bryan portfolio manager at Gradient Investments in Arden Hills, Minnesota, told Reuters. "Is it delayed or is it dead?"
In 1.13pm trading in New York, the Dow Jones Industrial Average dropped 1.3 per cent, while the Nasdaq Composite Index shed 1.7 per cent. In 12.58pm trading, the Standard & Poor's 500 Index retreated 1.1 per cent.
"We have an environment now where we don't speak about fiscal stimulus any more, we don't talk about corporate tax cuts any more," Commerzbank cross-asset strategist Max Kettner told Bloomberg. The divergence between low volatility in the markets and high volatility in Washington "is unlikely to last very long," he added.