Updates prices

By Ragini Mathur and Avinash P

July 21 (Reuters) - U.S. stock index futures rose on Tuesday, as semiconductor shares extended a recovery from a recent selloff, while investors awaited major tech earnings for clues on the future of the AI trade.

Markets also weighed mixed signals from the U.S.-Iran conflict after a senior Iranian official told Reuters on Monday that Tehran had received a proposal from mediators for a 10-day ceasefire.

Yemen's Iran-aligned Houthis said on Monday they ​would impose a naval blockade on Saudi Arabia, opening a potential new front against the United States in its war with Iran and raising the threat to global energy supplies and trade beyond the Gulf.

Brent crude futures returned to around $90 a barrel after earlier losses. O/R

Recently battered semiconductor stocks were leading premarket gains. The iShares Semiconductor ETF SOXX.O climbed 4%, rising for the second consecutive day.

"While shipping confidence and oil production may take longer than expected to be fully restored, we expect limited pass-through to core inflation, keeping central banks from tightening aggressively," said Mark Haefele, chief investment officer at UBS Global Wealth Management.

"This means earnings growth should remain a key driver of the equity market."

Lately, chip stocks have come under heavy pressure, as investors question whether this year's powerful rally in the sector has gone too far, and scrutinize the lack of tangible returns on hefty investments by hyperscalers.

The Philadelphia SE Semiconductor Index .SOX ended Friday more than 20% below its late-June record high, confirming a bear-market decline, though the index remains up about 66% for the year.

At 07:21 a.m. ET, Dow E-minis YMcv1 were up 155 points, or 0.3%, and S&P 500 E-minis EScv1 were up 30.25 points, or 0.4%. Nasdaq 100 E-minis NQcv1 were up 346 points, or 1.2%.

Recent volatility in chip stocks, which later spread to broader markets, pushed Wall Street's main indexes to three straight sessions of losses despite an upbeat start to the second-quarter earnings season and cooler inflation numbers.

Investor focus this week will turn to results from Alphabet GOOGL.O and Intel INTC.O, which could help determine whether the AI trade has further room to run amid elevated profit expectations.

Adding to the uncertainty, President Donald Trump on Monday unveiled 50% tariffs on a wide range of imports from Canada. The U.S. administration said the move was in response to Canada's treatment of American-made cars, alcohol and dairy goods.

The Financial Times reported that Trump is expected to impose fresh tariffs on dozens of countries as soon as this week, with his 10% global tariff poised to expire on Friday.

Among early movers, 3M MMM.N shares gained 5.4% after the industrial giant lifted its full-year profit forecast.

Nebius NBIS.O rose 6.5% after Nvidia NVDA.O disclosed a 9.3% passive stake in the AI cloud firm.

Equifax EFX.N dropped 12.4% after the credit ratings firm forecast annual profit below estimates.