Global tech sector sell-off knocks back European shares

* FTSEurofirst 300 down 0.7 pct

* Tech the top sectoral faller, echoing U.S., Japan

* Volatility ticks up

* Russia tensions rumble on, crimping appetite

By Alistair Smout

LONDON, April 11 (Reuters) - European shares slid at the open on Friday to leave them set for their first weekly loss in a month, tracking steep falls in Asian and U.S. stocks as equities came under pressure globally.

Technology stocks led sectoral falls with a 1.9 percent decline, echoing moves in the United States, where the tech-heavy Nasdaq 100 posted its biggest drop in two and half years, while the Japanese.

The sector in Europe had rallied over 40 percent from the beginning of November 2012 to the start of April this year.

Volatility, which measures the price that investors are willing to pay to protect against future falls and thus is seen as a gauge of "fear" in the market, ticked up 3.6 percent, having fallen after dovish noises from the U.S. Federal Reserve temporarily stabilised markets on Wednesday.

"If you see such a strong trend in the U.S., then it ultimately ripples through the other markets as well. We tried to stabilise midweek, but overnight it has continued," Veronika Pechlaner, who helps manage $13 billion of assets at Ashburton Investments, said.

The pan-European FTSEurofirst 300 fell 0.7 percent to 1,321.06, with no sectors in positive territory.

The falls left the index down 2.4 percent for the week and set for its first weekly fall in a month. A rally in the three weeks prior to this one had seen the FTSEurofirst 300 post its highest close since May 2008.

"We've recently taken a little bit out of equities. We like equities as an asset class in the medium term, but we have seen a bit of a retreat in the market recently," Pechlaner said.

Political tension further dampened investor appetite after Russian President Vladimir Putin warned the country's gas supplies to Europe could be disrupted if Moscow cuts the flow to Ukraine over unpaid bills, drawing a U.S. accusation that it was using energy "as a tool of coercion".

Shares in European blue-chips with the biggest exposure to Russia underperformed, with Austrian lender Raiffeisen Bank International down 2.3 percent.

Thales (Paris: FR0000121329 - news) slid for a second straight day, down 4 percent, after JP Morgan (Other OTC: JPYYL - news) downgraded Europe's largest defence electronics company to "neutral" from "buy" following a company investor day on Thursday.

"Thales' assumptions on sales and cost reduction through to 2017-18 were weaker than we expected... With the shares up 47 percent in the last 12 months, we see now see limited near-term upside," analysts at JP Morgan said in a note.

Europe bourses in 2014: http://link.reuters.com/pap87v

Asset performance in 2014: http://link.reuters.com/gap87v

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