The S&P 500 has ended lower on Thursday after a report that Pfizer Inc had slashed the target for the rollout of its COVID-19 vaccine.

The widely followed US stock benchmark fell from record highs late in the session after the Wall Street Journal reported that Pfizer faced supply chain obstacles related to the vaccine, sending its stock down.

Boeing Co jumped after budget airline Ryanair ordered 75 additional 737 MAX jets with a list price of $US9 billion ($A12 billion), throwing a commercial lifeline to the embattled US planemaker.

Tesla Inc surged after Goldman Sachs upgraded the stock to “buy” in the run-up to the electric car maker’s addition to the S&P 500.

Tesla was Wall Street’s most traded stock by value, with over $US22 billion ($A30 billion) worth of shares exchanged, according to Refinitiv data, more than double Boeing, in second place.

First-time US claims for jobless benefits fell last week, but remained extraordinarily high at 712,000, while a separate survey showed US services industry activity slowed to a six-month low in November.

“I don’t think we will see those numbers start to get back to normal until we start to see a rollout of a vaccine,” said Sal Bruno, chief investment officer at IndexIQ.

“The market is discounting that and saying we are looking forward to the first or second quarter and a rollout of the vaccine to the general population.”

US Senate Majority Leader Mitch McConnell cited some positive movement in congressional efforts to reach a compromise on a new coronavirus aid bill but gave no hints on when such a deal could be struck.

Progress in developing a working COVID-19 vaccine before the end of the year has driven Wall Street’s main indexes to record levels in recent days.

Despite the economic destruction caused by the pandemic, the S&P 500 has gained about 14 per cent in 2020.

Unofficially, the Dow Jones Industrial Average rose 86.71 points, or 0.29 per cent, to 29,970.5, the S&P 500 lost 2.24 points, or 0.06 per cent, to 3,666.77 and the Nasdaq Composite added 27.82 points, or 0.23 per cent, to 12,377.18.