The three major U.S. stock indexes closed higher Monday with the S&P 500 and the Nasdaq hitting intraday record highs, as the Street awaits the Federal Reserve's crucial policy meeting later this week.

Tesla shares climbed after regulatory filings revealed CEO Elon Musk had acquired nearly $1 billion worth of the electric vehicle maker's stock on Friday. And Google parent Alphabet hit a record high and raced past $3 trillion in market capitalization.

The Federal Open Market Committee meeting on September 16 and 17 looms large over sentiment this week with market participants widely expecting a 25-basis-point reduction following recent economic data signaling labor market weakness.

“The market is counting on sort of a goldilocks scenario where the employment market is just weak enough to prompt the Federal Reserve to start a rate cutting series, not just one, without disrupting overall growth,” said Carol Schleif, Chief Investment Officer at BMO Family Office. “I think the markets will be disappointed if the Fed doesn’t give some hint that they intend to continue rate cuts.”

Traders on Monday are pricing in a 96% chance of a 25-basis-point cut at this week's meeting.

Tesla's gains boosted the S&P 500 consumer discretionary sector to its highest level in nearly nine months. Meanwhile, Alphabet helped lift the communication services sector.

Nvidia slipped after China's market regulator said it will continue an investigation into the AI chip leader after preliminary findings showed it had violated the country's anti-monopoly law.

According to preliminary data, the S&P 500 gained 32.06 points, or 0.49%, to end at 6,616.35 points, while the Nasdaq Composite gained 209.37 points, or 0.95%, to 22,350.48. The Dow Jones Industrial Average rose 58.68 points, or 0.13%, to 45,892.90.

Wall Street's three main indexes had logged weekly gains in the previous session, with the Nasdaq and the S&P 500 hitting intraday record highs on Friday as technology-linked stocks remained resilient.

Declines in McDonald's and Procter & Gamble Co weighed on the Dow.

CoreWeave jumped after the data center operator signed a deal with Nvidia that guarantees that the chipmaker will purchase any residual cloud capacity not sold to customers. The deal's initial value is $6.3 billion. Kerrisdale Capital disclosed a short position on CoreWeave.