US stocks were little changed in early trade on Thursday, as traders waited to see details of a much anticipated tax plan.
US President Donald Trump is also expected to formally announce Federal Reserve governor Jerome Powell as his pick to lead the US central bank.
The Nasdaq Composite dropped 11 points to 6,705.5.
US stocks have surged this year, a rally analysts say is due to strong global growth and healthy corporate earnings.
Shareholders are also anticipating benefits from proposed changes to the US tax code, which would lower taxes for businesses.
Republicans are expected to release details of the plan on Thursday, although doubts remain about whether they will secure enough votes to approve it.
There are fewer doubts about Mr Powell, whom markets view as a moderate Republican likely to keep Fed policies in line with the current Fed chair, Janet Yellen.
Under Ms Yellen, interest rates have increased gradually amid signs of economic improvement.
Financial companies, whose fortunes are closely tied to the cost of borrowing, saw some of the strongest gains on Thursday.
Shares in Goldman Sachs climbed 0.7%, while JP Morgan Chase and American Express rose by more than 0.2%.
Shares in Newell Brands, which makes Rubbermaid and Sharpie pens, plunged more than 20% after the company said sales during the third quarter had fallen 7% year-on-year to $3.7bn.