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Indexes up: Dow 0.65%, S&P 500 0.64%, Nasdaq 0.95%

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AES ( AES ) jumps on report of potential sale efforts

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UnitedHealth ( UNH ) down on report of DOJ probing co's Medicare

billing

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Nvidia ( NVDA ) becomes first company to hit $4 trillion in market

value

(Updates with market open prices)

By Pranav Kashyap and Nikhil Sharma

July 9 (Reuters) -

Wall Street's main indexes climbed higher on Wednesday, with

Nvidia ( NVDA )

soaring

to a $4 trillion valuation, while investors shrugged off

President Donald Trump's latest tariff salvo.

Nvidia ( NVDA ) rose 2.2% to become the first company to

ever hit $4 trillion in market value, solidifying its position

as one of Wall Street's most-favored stocks to tap in the

ongoing surge in demand for artificial intelligence

technologies.

At 9:47 a.m. ET, the Dow Jones Industrial Average

rose 286.20 points, or 0.65%, to 44,526.96, the S&P 500

gained 39.70 points, or 0.64%, to 6,265.22 and the Nasdaq

Composite gained 195.72 points, or 0.95%, to 20,614.19.

Seven of 11 S&P sectors clocked gains, with the technology

index leading the pack with a 1.2% rise.

Trump ramped up his trade offensive on Tuesday,

announcing a 50% tariff on copper and vowing to slap

long-threatened levies on semiconductors and pharmaceuticals.

This came just a day after he jolted 14 trading partners

with a fresh wave of tariff warnings, and said that at least

seven new notices would drop later in the day.

The market's reaction to the latest salvo was in contrast

with Monday's selloff - triggered by the White House's new

tariff threats against Japan and South Korea.

With tariff deadlines now pushed to August 1, investors are

pinning their hopes on negotiations to avert a full-blown trade

war.

"The tariff issue continues to be this sort of seesaw and

because of that back-and-forth, it obviously has given investors

a bit of a calm," said Philip Blancato, chief market strategist

at Osaic Wealth.

"Markets will react if they see an impact of tariffs in

second-quarter earnings next week. But if earnings continue to

improve, that just gives them an even longer wait for the tariff

negotiations to get finalized," said Ross Bramwell, investment

strategist at Homrich Berg.

Meanwhile, after last week's record closes for the S&P 500

and the Nasdaq - buoyed by a surprisingly robust jobs report

-investors are turning their attention to Thursday's initial

jobless claims for the next pulse check on the labor market.

Traders will also parse through the minutes from the Federal

Reserve's June meeting, due at 2:00 p.m. ET, for any hints about

when policymakers might resume easing rates.

While a July rate reduction is almost fully ruled out, the

odds of a September cut stand at about 66%, according to CME

Group's FedWatch tool.

Trump's erratic tariff actions have sparked concerns about

global growth and inflation, while also complicating the work of

the Fed, which has adopted a wait-and-see approach on monetary

policy.

Among stocks, AES Corp ( AES ) rose 14.3% after Bloomberg

reported that the power provider was exploring options,

including a sale.

Health insurer UnitedHealth Group ( UNH ) slipped 2% after

the Wall Street Journal reported that the U.S. Department of

Justice was investigating how the company deployed doctors and

nurses to gather diagnoses that increased its Medicare payments.

Shares of U.S. advertising firms Interpublic and

Omnicom ( OMC ) fell over 1.5% each, after peer WPP ( WPP )

slashed its annual profit guidance.

Advancing issues outnumbered decliners by a 2.34-to-1 ratio

on the NYSE. There were 70 new highs and 12 new lows on the NYSE

and by a 2.23-to-1 ratio on the Nasdaq.

The S&P 500 posted 10 new 52-week highs and three new

lows while the Nasdaq Composite recorded 31 new highs and 21 new

lows.