June 15 (Reuters) - The pan-European STOXX 600 index hit a new record high on Monday, boosted by gains in most sectors after the United States and Iran reached a preliminary agreement that would reopen the Strait of Hormuz and end the three-month-old war in the Middle East.

Brent crude fell to its lowest level in three months, while the European Stoxx 600 index closed 0.2 percent higher, recovering losses incurred since the outbreak of the war on February 28, after US President Donald Trump, Vice President J.D. Vance and Iranian Parliament Speaker Mohammad Baqer Qalibaf signed a memorandum of understanding to end the war.

The index surpassed its peak recorded on February 27.

Stocks in Europe have underperformed less than their counterparts in the United States and Asia since March, largely due to the continent's reliance on the Strait of Hormuz for vital oil supplies and its lower exposure to artificial intelligence technology stocks.

Thanks to today's gains, the European Stoxx 600 index has jumped 7.2 percent this year, narrowing the gap between it and the US Standard & Poor's 500 index, which has advanced by more than 10 percent.

“Perhaps it’s time to see some shift,” said Michael Field, senior European equity strategist at Morningstar. “You may have made gains in some AI stocks that have risen sharply over the past month or two, and you could reinvest that in areas such as defense in Europe, which have suffered losses.”

Spain's IBEX 35 index led gains among the region's major indices, rising to a record high of 1.4 percent. Germany's DAX index advanced 1.1 percent, reaching its highest level in nearly two weeks. France's CAC 40 index climbed 0.4 percent to pre-war levels.

Banking stocks were among the biggest contributors to the rise of the Stoxx 600 index, advancing 1.5 percent to their highest level since January 2008. Shares of car companies, which are highly sensitive to volatile energy prices, rose 2.6 percent, while shares of airlines such as Lufthansa and Air France jumped 4.5 percent and 3.4 percent respectively.

Nevertheless, analysts expect energy costs to remain high until flows gradually return to pre-war levels. Last week, concerns about energy-driven inflation prompted the European Central Bank to raise interest rates by 25 basis points.