LONDON, May 22 (Reuters) - A strong rally in tech stocks has largely gone under the radar against a darkening backdrop for European equity markets as the energy shock triggered by the Iran war dampens economic growth.

The war has paused "Make Europe Great Again" trades, with the region's shares expected to underperform U.S. peers as long as it persists. Data shows euro zone economic activity fell at its sharpest rate in more than two-and-a-half years in May.

Yet research from TS Lombard shows two baskets of AI-related shares account for more than two-thirds of the positive performance in European stocks over the past month and a half.

"The performance of our EU AI baskets since April is on par with the Nasdaq, just a touch behind Taiwan," said TS Lombard European and global macro director Davide Oneglia, referring to the U.S. index and Taiwan's bourse.

"Look through macro chaos and don't ignore European AI winners," Oneglia added.

One TS Lombard AI basket, made up of firms in the semiconductor supply chain such as ASML, Infineon and STMicroelectronics, has rallied by roughly 20% since the start of April.

The other, up around 22%, is made up of companies in the AI infrastructure buildout such as data centres and includes Schneider Electric and Italy's Prysmian.

Gains in European tech shares are dwarfed by a 55% rise in the South Korean index over the same period, LSEG data shows. The Nasdaq 100 is up by roughly 21% and Taiwanese stocks have rallied by around 28%, the TS Lombard report shows.

AI INFRASTRUCTURE BOOST

A renewed focus on AI, highlighted by strong U.S. tech earnings since early April, as well as a push by Europe to support tech infrastructure suggest the European tech share rally could have further to run.

Seema Shah, chief global strategist at Principal Asset Management, which manages around $578 billion, noted Europe's renewed focus on innovation which has begun to show in the last two years in defence, energy security and AI infrastructure.

"You are seeing capital expenditure into those areas. We do think that those kinds of secular themes have remained pretty strong and probably have been actually reinforced by the conflict," said Shah.

Even after recent gains, European tech shares have a cheaper valuation than U.S. competitors. The European tech stocks sub-index trades at almost 28 times expected earnings, compared with almost 35 times for the Nasdaq.

Oneglia said his analysis of European AI stocks focused on the post-April period because that is when the AI theme resurfaced globally, with strong earnings and investors changing their minds on whether AI spending plans were excessive or not.

U.S. tech bellwether Nvidia ( NVDA ) on Wednesday released first-quarter revenue that beat Wall Street expectations.

While Europe's STOXX 600 index has fallen just over 2% since the Iran war began on February 28, the region's tech shares have surged 10% and this week hit their highest level since 2000.

Tech makes up just 10% of the European benchmark, which is dominated by financials, industrials and healthcare.