By Kanchana Chakravarty and Nikhil Sharma

(Reuters) -U.S. stock futures were flat on Wednesday, as a ceasefire between Israel and Iran appeared to be holding and investors awaited more comments from Federal Reserve Chair Jerome Powell.

The Nasdaq 100 closed at a record high on Tuesday and all three major indexes gained more than 1% as the de-escalation in Middle East hostilities supported risk sentiment. The benchmark S&P 500 index was less than 1% below its all-time peak.

Despite isolated violations of the ceasefire brokered by U.S. President Donald Trump a day earlier, investors remained optimistic that the truce between the two warring nations would last.

"So a lot of our major concerns, at least for right now, shifted into neutral as compared to being headwinds ... that puts this in a place where we'll take a wait-and-see attitude," said Art Hogan, chief market strategist at B Riley Wealth.

"We've heard what Jerome Powell said at Capitol Hill and will likely repeat that today. We get the sense that the Israel and Iran situation is going to de-escalate from here."

In the second day of Powell's congressional testimony, scheduled at 10:00 a.m. ET, investors will look for any hints on the central bank's monetary policy path.

This comes a day after Powell emphasized the Fed's wait-and-watch approach to interest rates as tariff-led price pressures kick in. However, he also said a lower-than-expected inflation reading or weakness in the labor market would push the central bank to cut sooner.

Meanwhile, a surprise deterioration in U.S. consumer confidence on Tuesday kept the door open for an immediate rate cut in July.

Money market moves show traders are pricing in about 60 basis points of rate cuts by the end of 2025, with a 70% chance of a 25-bps rate cut in September, according to CME Group's FedWatch tool.

At 07:06 a.m. ET, Dow E-minis were down 37 points, or 0.09%, and S&P 500 stock futures were up 0.02%. Nasdaq 100 E-minis were up 41 points, or 0.18%.

Shares of delivery giant FedEx fell 5.5% in premarket trade after the company forecast quarterly profit below estimates as tariffs weighed on global demand. Rival UPS dropped 1.1%.

Investors were also watching developments from a meeting of NATO leaders, as European allies gathered to pledge a big increase in defense spending at a short summit tailor-made for Trump.

Trump, who reiterated his commitment to the alliance, has often threatened not to protect NATO members if they fail to meet spending targets.

The Commerce Department's final take on first-quarter GDP is due on Thursday, while Friday's Personal Consumption Expenditures (PCE) report will help investors ascertain the economic effects of Trump's tariffs that have kept global markets on edge since the start of the year.