Tenaris leads European shares lower after U.S. trade ruling

* FTSEurofirst 300 down 0.1 pct, Euro STOXX 50 down 0.1 pct

* Weak start on Wall St provides no boost for euro shares

* Tenaris (Milan: TEN.MI - news) , Vallourec (Xetra: VAC.DE - news) pummelled by U.S. import tariff ruling

* Carlsberg (Other OTC: CABGY - news) , Lafarge (Munich: CIL.MU - news) shrug off EM hit with strong updates

By Alistair Smout and Joshua Franklin

LONDON, Feb 19 (Reuters) - European shares edged lower on Wednesday, led by Italy's Tenaris as a U.S. tariff ruling hurt the region's steel pipe industry, although buoyant updates from brewer Carlsberg and Lafarge helped limit market losses.

The FTSEurofirst 300 opened slightly higher, but gave away gains as the session went on, unable to mount a recovery as caution ahead of the U.S. Federal Reserve minutes and weak housing data prompted falls in U.S. stocks.

"The weaker housing market data coming out of the U.S. could indicate towards a prolonged slowdown of momentum," Kash Kamal, research analyst at Sucden Financial, said.

"European equities will take the lead from Wall Street and if today's (Fed) meeting minutes fail to provide the necessary reassurance we could see a subsequent pull back."

Seamless steel tube maker Tenaris fell 6.4 percent to the bottom of the pan-European FTSEurofirst 300 index after U.S. trade authorities decided not to impose tariffs on South Korean imports of oil and gas pipe. French peer Vallourec fell 4.6 percent.

Tenaris and Vallourec, which respectively generate 49 percent and 29 percent of their sales in North America, had signed a petition complaining that manufacturers in South Korea and other countries were selling pipe in the United States at unfairly low prices.

"Many people in the market were thinking that the key for improving the pricing power would be some reduction in the imports coming from South Korea," said Julien Laurent, energy equity analyst at Natixis (Paris: FR0000120685 - news) .

"I assume that the consensus will have to downgrade its estimates (of future earnings per share) a bit. I would say for Tenaris it would be more than 5 percent."

The Italian blue-chip FTSE MIB underperformed peers even as optimism over a new government kept yields at 8 year lows, with the drop in Tenaris accounting for half of its decline.

At 1455 GMT, the FTSEurofirst 300 index of top European shares was down 0.1 percent at 1,335.38 points, while the euro zone Euro STOXX 50 index was down 0.1 percent at 3115.25 points.

Both indexes were retreating from overbought territory based on their seven-day Relative Strength Index, a momentum indicator, after rising for eight of the last 10 sessions.

The FTSEurofirst 300 has gained roughly 5 percent over the past two weeks.

"The indices right now are somewhat toppish and we're looking for a short-term reversal, possibly before the end of the week," Valerie Gastaldy, head of technical analysis firm Day-By-Day, said, adding that the Euro Stoxx 50 could hit 3,050 by Friday.

"(It's) not necessarily that deep but we had a very steep rise."

Better earnings news helped to support the market. Shares in Carlsberg surged 6.3 percent as the world's fourth largest brewer raised its dividend by a third thanks to growth in Western Europe and Asia offsetting sluggish sales in Russia, where the economy is slowing.

Lafarge, which derives 58 percent of its sales from emerging markets, confirmed its targets despite a hit from volatile currencies in the fourth quarter, betting on continued growth in emerging markets and a recovery in North America and Europe. Its shares rose 3.1 percent.