GLOBAL MARKETS-Stock indexes ease with tech shares while oil prices gain?

* U.S. stock indexes mostly down slightly

* Oil prices gain as Iran worries continue

* Longer-dated U.S. Treasury yields off recent highs (Updates to midday)

By Caroline Valetkevitch and Samuel Indyk

NEW YORK/LONDON, May 18 (Reuters) - Major stock indexes mostly eased as technology shares fell on Monday, while oil prices climbed following more worries over supply disruption from the Iran war.

Longer-dated U.S. Treasury yields dipped after climbing to their highest level in over a year in overnight trading.

Sovereign bond yields have risen sharply recently as investors worry the war in Iran that began in late February may bring a lasting inflationary shock.

Iran sent a new peace proposal to the United States with terms that appeared similar to offers Washington has previously rejected, although a senior Iranian official told Reuters on Monday that the U.S. had softened positions on some issues.

A Pakistani source confirmed that Islamabad had shared the latest proposal with Washington. But the source suggested progress had been difficult.

U.S. crude was last up 1.32% at $106.81 a barrel.

Investors are focused on the tech sector's recent sharp gains and are bracing for results from Nvidia (NVDA) this week.

The tech sector, down 1.4%, led sector declines in the S&P 500.

U.S. President Donald Trump's recent trip to China "left a lot of open questions about the future of Taiwan and whether or not the United States would be there to protect it," said Oliver Pursche, senior vice president, advisor for Wealthspire Advisors in Westport, Connecticut.

"Given Taiwan's significance to the chip market, that partially explains the selloff we're seeing in that sector today," he said, adding that investors are also taking profits.

Trump's first visit to Beijing since 2017 ended on Friday with no major breakthroughs on trade or tangible help from Beijing to end the U.S.-Israeli war on Iran.

The Dow Jones Industrial Average fell 4.47 points, or 0.01%, to 49,521.70, the S&P 500 fell 21.33 points, or 0.29%, to 7,387.17 and the Nasdaq Composite fell 171.47 points, or 0.65%, to 26,053.68.

MSCI's gauge of stocks across the globe fell 2.72 points, or 0.25%, to 1,096.28. The pan-European STOXX 600 index rose 0.54%.

Rising yields push up borrowing costs and mean a higher discount for future company earnings, challenging stock valuations.

The yield on benchmark U.S. 10-year notes dipped to about 4.594% after hitting 4.631% in overnight trading.

Earlier, Japan's 10-year yield hit a peak not seen since 1996 as the government proposed to issue fresh debt to fund a planned extra budget to cushion the economic blow from the Iran war. Germany's 10-year bond yield rose to a level not seen in 15 years.

AI, RETAIL EARNINGS TO TEST STOCKS' RECENT RALLY

The artificial intelligence trade will be tested by earnings from Nvidia (NVDA) that are due on Wednesday, with expectations sky-high for the world's most valuable company.

Nvidia (NVDA) shares are up sharply since a March low, while the Philadelphia SE semiconductor index has also surged amid demand for chips as tech companies spend massively to build AI-related infrastructure.

Also due this week are results from a host of retailers, including Walmart (WMT), which will provide an insight into how consumers are faring with high energy prices. The dollar slipped against most major currencies as U.S. Treasury yields were off recent high levels.

The dollar index, which measures the greenback against a basket of currencies including the yen and the euro, fell 0.35% to 99.02.

(Reporting by Caroline Valetkevitch in New York and Samuel Indyk in London; additional reporting by Wayne Cole; Editing by Sharon Singleton and Nick Zieminski)