A volatile session put paid to earlier gains, as Wall Street tickers gave up advances to leave the field little changed on the day in thin late session volumes as Yellen euphoria fizzled out.
The Nasdaq Composite ended just 0.35% higher at 4,283.59 while the S&P500 was unchanged at 1,851.86. The Dow Jones Industrial Average, which also was higher on euphoria with Federal Reserve Chairman Janet Yellen's comments to Congress about US rate policy, came off and closed down 0.6% at 15,914.74.
Earlier, markets were buoyed by remarks from Yellen who indicated the central bank had flexibility on its side in monetary policy.
Yellen said conditions in the United States would allow the Fed to proceed with gradual adjustments to policy. That language was enough to placate those worried that global strife might halt rate hikes, while satisfying those worried about the rising cost of corporate credit that any tightening of policy would not burn a hole in company coffers.
Oil played its part in the downfall of bourses into the close, with the US benchmark future, the West Texas Intermediate falling 1.86% to US$27.42.
All three major US share tickers rose on Wednesday for the first time this month after Federal Reserve Chairman Janet Yellen indicated the central bank had flexibility on its side in monetary policy.
In a testimony to Congress, Yellen said conditions in the United States would allow the Fed to proceed with gradual adjustments to policy. That language was enough to placate those worried that global strife might halt rate hikes, while satisfying those worried about the rising cost of corporate credit that any tightening of policy would not burn a hole in company coffers.
US financial stocks, which in recent days had been hit on worries over the impact of low interest rates on banks' profitability and capital strength, were among the stocks to rise mid-session.
The Nasdaq Composite led the gains, up 1.6% at 4,337.98, while the broad S&P500 advanced 0.9% to 1,868.97. The blue-chip Dow Jones Industrial Average was up 0.12% to 16,033.90.
US shares, like European indices, started Wednesday on the front foot as Fed chair Janet Yellen gave a testimony before Congress, outlining current conditions and the potential US response.
The benchmark Dow Jones is up 75 points at 16,090 and the S&P500 gained 14 to 1,866. The tech heavy Nasdaq is 55 points higher at 4,325.
In London, at the time of writing, Footsie is 36 ahead at 5,672 and the oil price for US crude has eased 0.75% down, after going higher overnight.
Yellen's words are being closely listened to as traders are keen to hear what next for US interest rates after the foot came off the brake pedal at the end of last year - with the first rise.
As the economy grows along with the Labour market and inflation, the central bank has looked to tighten policy but Yellen said today that with so much uncertainty and volatility about, rates may stay lower ...for longer...
“Foreign economic developments, in particular, pose risks to US economic growth,” Ms Yellen was quoted as saying.
Referring to the slump in oil and commodities, she said this could spark financial stress in commodity-exporting economies, particularly in emerging markets, but conversely, could help economic growth as customers benefit from cheap energy.
Meanwhile, in company news, Disney (NYSE:DIS) shares continued the slide started after hours as its results for the quarter were not well received by the market, despite Star Wars sparking a profit rise.
Shares are down 3.5% to US$89.09.