Wall Street futures were flat to slightly lower on Wednesday, as markets were guarded ahead of a widely anticipated interest-rate cut from the Federal Reserve later in the day, and Nvidia dipped after a report Chinese tech firms might stop buying its chips.

The U.S. central bank is expected to reduce borrowing costs by at least 25 basis points at 2 p.m. ET, a move priced in by investors after a series of economic indicators indicated a weakening jobs market.

Markets will closely watch Chair Jerome Powell's speech as well as the "dot plot" projections to gauge the extent of interest-rate cuts that could be delivered this year and the next.

Traders are expecting a rate reduction totaling about 68 bps by the end of the year, according to data compiled by LSEG.

"Investors will be watching whether Fed officials push back against market expectations for a series of rate cuts extending into next year," analysts at UBS Global Wealth Management said.

"Any hawkish element could challenge the currently positive investor sentiment and trigger market volatility."

Meanwhile, Nvidia fell 1.7% in premarket trading after the Financial Times reported that China's internet regulator had instructed the country's biggest tech companies to stop buying all of the AI leader's chips.

At 7:42 a.m. EST, Dow E-minis were up 16 points, or 0.03%, S&P 500 E-minis were down 4.5 points, or 0.07%, and Nasdaq 100 E-minis were down 20.25 points, or 0.08%.

The Fed meeting will be a test of Wall Street's recent rally, with the S&P 500 and the Nasdaq hitting record highs in the last six sessions, boosted by rate-cut expectations and revived enthusiasm around AI-stock-linked trading.

Wall Street's main indexes have gained so far in September, a month deemed bad historically for U.S. equities. The benchmark S&P 500 has shed 1.5% on average since 2000, data compiled by LSEG showed.

New Fortress Energy soared 42.5% before the bell after the company reached an agreement to supply liquefied natural gas to the Puerto Rican government.

Workday gained 8% after activist investor Elliott Management said on Tuesday it had built a stake of more than $2 billion in the human resources software provider. (Reporting by Purvi Agarwal and Sukriti Gupta in Bengaluru; Editing by Pooja Desai)