The broad S&P 500 index fell 0.2 percent, the Dow Jones industrial average fell 0.1 percent and the Nasdaq's technology-heavy composite index lost 0.6 percent.
The market was weighed down by declines in some of the big tech companies linked to artificial intelligence. Among the losers were Broadcom and Oracle, down 5.6 percent and 2.7 percent, respectively.
On Tuesday, new labor market statistics will be released, with analysts predicting that more jobs were created than lost in November. And on Thursday, inflation figures will be released, with the price increase expected to reach 3.1 last month.
Shares in electric car maker Tesla were up, nearing their record high of $479.86 from December last year. But Monday's gain was limited to 3.6 percent, so the stock closed at $475.31.
