* FTSEurofirst 300 index flat; trading choppy
* Strong crude prices, euro zone debt weigh on equities
* Technology stocks gain after TI-NatSemi deal
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By Harpreet Bhal
LONDON, April 5 (Reuters) - European shares traded flat in choppy trade on Tuesday with inflation concerns intensifying as crude prices hovered around 2-1/2 year highs, prompting investors to pause for breath following a three-week rally.
By 0918 GMT, the pan-European FTSEurofirst 300 index of top shares was flat at 1,141.75 points in a choppy session, with the index having gained around 7 percent since hitting 3-1/2 month lows in mid-March.
Brent crude prices held at around $121 a barrel on geopolitical uncertainties in parts of the Middle East and Africa, stoking inflation concerns ahead of a European Central Bank (ECB) meeting later this week, when it is expected to raise rates by 25 basis points.
"It (the strong crude price) is the reason why the ECB is expected to hike rates this week. The worry is whether it's going to be generally an influence on higher interest rates," said Bernard McAlinden, investment strategist at NCB Stockbrokers.
Technical indicators suggested the equity market could make modest gains in the near term, with the Eurostoxx 50 index staying above its 50-day moving average and the support level of the 61.8 percent Fibonacci retracement from a high in mid-February to a low in mid-March.
"We're somewhere in the middle of a cyclical bull market and on that basis the markets can push higher but these things come in phases and there are more enduring challenges such as geopolitical uncertainty affecting the oil price," said McAlinden.
Falls in peripheral euro zone equities weighed on the market as debt concerns returned to the fore after Moody's cut Portugal's sovereign debt by one notch and said the upcoming government would need to seek financial aid as a matter of urgency.
The Thomson Reuters peripheral euro zone index lost 0.6 percent, with banking shares Santander down 1.5 percent, Millennium bcp down 1.2 percent and Credit Agricole down 2 percent.
TECH SHARES GAIN
On the upside, gains in technology firms helped support the index, with chipmakers rising after Texas Instruments agreed to buy National Semiconductor Corp for $6.5 billion, paying a rich 78 percent premium.
Infineon Technologies rose 3 percent to the top of the FTSEurofirst 300 gainers list, while STMicroelectronics added 2.9 percent.
Some caution prevailed as investors awaited the release of the Federal Open Market Committee's minutes from its meeting of March 15, due at 1800 GMT, to get more insight on the outlook for U.S. interest rates.
Fed Chairman Ben Bernanke said that U.S. inflation was driven primarily by rising commodity prices and was unlikely to persist while other Fed officials have expressed a range of sentiments in recent weeks for and against keeping the central bank's $600 billion bond-buying program going in light of a modest recovery in the economy.
Strategists said the equity market could start to experience a shift out of cyclical stocks and into defensive names partly due to factors such as monetary tightening, peaking leading indicators and inflation.
"Quantitative easing in the U.S. is probably going to be withdrawn at some stage in June," said Thierry Serero, a fund manager at Octopus Investment.
"That has been the main driver in the economic recovery and nobody knows the effect of withdrawing that stimulus so the market will probably try to be a bit more cautious," he said, adding that the scenario was supportive for defensive sectors such as healthcare, telecoms and utilities." (Editing by Hans Peters)