* Indexes off: Dow 0.24%, S&P 500 0.71%, Nasdaq 1.17%

* Trump mulls Kharg Island takeover, report says

* Main indexes on track for fourth-straight weekly loss

* FedEx ( FDX ) up on strong forecast; Amazon ( AMZN ) plans smartphone

comeback

(Updates for market open, adds analyst comments)

By Johann M Cherian and Utkarsh Hathi

March 20 (Reuters) - Wall Street's main indexes slipped

on Friday as the Iran war approached its fourth week, roiling

energy markets and prompting investors to aggressively reprice

bets on the Federal Reserve's interest-rate cuts.

The conflict in the Middle East showed no signs of easing as

Iran attacked an oil refinery in Kuwait and a report said that

the Trump administration is planning to occupy or blockade

Iran's Kharg Island to pressure Iran to reopen the Strait of

Hormuz.

Investors also weighed major nations' efforts to ease energy

supplies. Brent prices wobbled throughout the day and were last

at $108 a barrel.

Offering some comfort, FedEx ( FDX ), often seen as a

barometer of business activity, issued upbeat forecastsand said

global demand was holding steady despite geopolitical tensions,

sending its shares up 3.4%. Rival United Parcel Service ( UPS )

added 0.6%.

Still, investors are weighing the impact of higher oil

prices on corporate earnings, as the first quarter comes to an

end.

"The longer this goes on, you're going to start to see

companies report in earnings that they've had price pressures

and it could be all through the chain," said Joe Saluzzi,

co-head of equity trading at Themis Trading.

A flurry of central bank decisions this week along with the

Fed acknowledged how the conflict had complicated policymaking.

Fed Governor Christopher Waller said he was planning to dissent

in favor of a rate cut at the central bank's meeting due to

unexpected job losses until a developing oil shock raised

inflation risks.

While U.S. policymakers are still penciling in at least one

quarter-point interest rate cut this year, markets are less

convinced. Traders have pushed their bets for a rate cut to

sometime in 2027, from December 2026 earlier this month,

according to LSEG-compiled data.

At 9:58 a.m. ET, the Dow Jones Industrial Average

fell 110.31 points, or 0.24%, to 45,911.12, the S&P 500

lost 46.58 points, or 0.71%, to 6,559.91 and the Nasdaq

Composite lost 259.01 points, or 1.17%, to 21,831.68.

Wall Street's fear gauge, the CBOE volatility index,

spiked 1.25 points to 25.31.

Seven of the 11 S&P 500 sector indexes were in the red, led

by consumer discretionary's 1.2% drop.

Friday also marks the once-in-a-quarter simultaneous expiry

of derivatives contracts tied to stocks, index options and

futures, also known as "triple witching," which can boost

trading volume and aggravate volatility.

All three main indexes were heading for their fourth

straight week of losses and were below their 200-day moving

average, a technical indicator reflecting long-term momentum.

The small-cap-focused Russell 2000 index slipped 0.7%

and had briefly touched a 10% drop from all-time highs earlier

this week.

Super Micro Computer ( SMCI ) tumbled 28.6% after three

people associated with the artificial intelligence server maker

were charged with smuggling at least $2.5 billion of AI

technology to China.

Rival Dell advanced 4.3%.

Gains have been strong in energy stocks, with the S&P 500

sector index set for its 13th straight weekly winning

streak, the longest on record, as geopolitical events in

Venezuela and the Middle East dominated much of the first

quarter.

Halliburton ( HAL ) was up marginally and Cheniere Energy

added more than 1%.

Amazon ( AMZN ) slipped over 1%. Reuters reported that the

megacap introduced its first smartphone, hoping to take on Apple

and Samsung.

Declining issues outnumbered advancers by a 3.22-to-1 ratio

on the NYSE and by a 2.48-to-1 ratio on the Nasdaq.

The S&P 500 posted eight new 52-week highs and 15 new lows,

while the Nasdaq Composite recorded 21 new highs and 98 new

lows.