March 19 (Reuters) - U.S. stock index futures slipped on Thursday as crude prices soared on intensifying hostilities in the Middle East, fanning inflation worries that have prompted the Federal Reserve to take a more cautious stance on interest rate cuts this year.

A strong forecast from Micron Technology also failed to uplift sentiment, with its shares down 4.5% in premarket trading, as investors mulled the chip company's higher spending plans in the light of elevated borrowing costs. 

Other memory chip stocks that had a strong run this year were also knocked down. SanDisk fell 4.5%, Western Digital slipped 2.3%, while AI leader Nvidia dipped 0.4%.

Brent crude prices hit $115 a barrel after Iran attacked energy facilities across the Middle East in retaliation to Israel's strike on its South Pars gas field. The U.S. benchmark, however, was trading at its widest discount to Brent in 11 years due to releases from U.S. strategic reserves and higher freight costs. 

The Fed left rates unchanged on Wednesday and Chair Jerome Powell flagged higher inflation ahead. He also said it was too soon to gauge the repercussions of the war on the economy and stuck to the prior forecast of one 25-basis-point rate cut this year.      

Morgan Stanley joined Goldman Sachs and Barclays in pushing back its forecast for an interest rate cut to September from June. Traders had priced out any expectations for a rate cut this year even before the Fed's verdict and LSEG-compiled data points to a dovish move only in mid-2027.

"The big takeaway from the Fed decision is that the Fed will not be riding to the economy's rescue, even if gas and diesel prices keep rising," said Bill Adams, chief economist for Comerica Bank.

"Monetary policy can slow growth and inflation, or it can speed up growth and inflation. But it can't offset an energy supply shock, which weakens growth at the same time that it raises inflation."

At 05:27 a.m. ET, Dow E-minis were down 135 points, or 0.29%, S&P 500 E-minis were down 22.25 points, or 0.34%, and Nasdaq 100 E-minis were down 118.25 points, or 0.48%.

Stocks and bonds sold off following the Fed verdict, sending the Dow and Nasdaq below their 200-day moving averages (DMA), while the benchmark S&P 500 hit a four-month low, putting it just a whisker away from breaching its own long-term moving average. The 200 (DMA) is a technical indicator reflecting long-term momentum. 

Investors will be keen on any potential commentary from policymakers later in the day, along with the weekly report on jobless claims.

Also in focus will be a U.S.-Japan summit that President Donald Trump may use to press for help on the war in Iran after his earlier call on allies to safeguard passage through the strategic Strait of Hormuz went unanswered. 

Energy price-sensitive travel stocks such as Delta Air and United were marginally lower, while cruise stocks such as Norwegian and Carnival were muted.

Expectations for higher interest rates and a stronger dollar weighed on prices of precious metals, sending miners such as Gold Fields and Endeavour Silver down around 9% each.

(Reporting by Johann M Cherian in Bengaluru; Editing by Devika Syamnath)