June 1 (Reuters) -

What matters in U.S. and global markets today

By Mike Dolan, Editor-at-Large, Finance and Markets

A new month, but the same market obsessions. Iran and AI continue to compete for investors' attention, with the latter winning out for now, as last week's momentum looks set to continue into Monday.

I'll get into that and more below.

But first, listen to the latest episode of the Morning Bid daily podcast. Subscribe to hear Reuters journalists discuss the biggest news in markets and finance seven days a week.

AI AND 1984

Last week's U.S.-Iran peace plan hopes ran into sand over the weekend and the two sides exchanged fresh military exchanges, while Israel advanced its incursion into Lebanon in its fight against Tehran-backed Hezbollah.

U.S. President Donald Trump reiterated claims on Monday that Iran wanted to strike a deal, but whatever happens on the diplomatic front, there's been no relief in the Gulf, and June is a crunch month for energy supplies. Brent crude pushed back up over 3% to trade at around $94 per barrel, after a 2% fall on Friday.

But the AI frenzy continued unabated. Nvidia's Jensen Huang on Monday unveiled a new chip that puts AI capabilities directly into laptops and desktop computers, which experts say will overhaul how users engage with AI.

Meantime, shares of South Korea's Samsung added another 10% on Monday, feeding off a mix of news, from the start of shipments of its new HBM4E chip to expectations surrounding a meeting with Nvidia's Huang later this week. South Korean shares rose more than 4%.

If there was any doubt about how real the global demand for chips is, official data on Monday showed South Korean exports surged by more than 50% year-on-year in May, the fastest annual pace since 1984.

It was a different picture in China, where factory growth stalled in May, according to the latest official survey, as export demand fell. There were also reports that Washington has moved to halt Nvidia chip shipments to Chinese subsidiaries located outside of China.

The ISM's U.S. manufacturing survey for May is due for release later today. That will kick off another big week for macro data, with the U.S. employment report for May due on Friday.

There's a slight weariness with the dominant themes among analysts, but June will add other factors to weigh. Central bank meetings this month could deliver interest rate rises, while a critical UK by-election will sharpen focus on a brewing leadership challenge there.

And there may even be appetite to look at other stock sectors. Even though tech has hogged the attention lately with its blistering stock moves - like Dell's latest explosive rise last week - the Russell 2000 small-cap index has done at least as well as the SOX chip index so far this year.

Revolution Medicines' shares surged 20% ahead of Monday's bell after trials of its pancreatic cancer drug showed it doubled the chances of survival from the disease.

Chart of the day

South Korea's exports grew more than expected in May at the strongest annual rate in over four decades, as a global boom in AI investment drove chip sales to a record, swelling optimism on the trade-reliant economy.

Exports from Asia's fourth-largest economy, a bellwether for global trade, rose 53.2% from a year earlier to a record high of $87.75 billion, preliminary trade data showed on Monday.

It was the 12th consecutive month of exports growing on a year-on-year basis and the biggest percentage rise since January 1984. The country's benchmark KOSPI stock index has more than doubled so far this year.

Today's events to watch

* U.S. ISM and S&P Global manufacturing PMIs for May (9:45-10 a.m. EDT)

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Opinions expressed are those of the author. They do not reflect the views of Reuters News, which, under the Trust Principles, is committed to integrity, independence, and freedom from bias.

(By Mike Dolan; Editing by Emelia Sithole-Matarise)