* Pan-European FTSEurofirst 300 index up 0.9 percent
* Index hits highest level since August
* Infineon soars after results, dividend beat expectations
* Wall Street shut for Thanksgiving (Recasts with new high)
By Danilo Masoni and Alistair Smout
MILAN/LONDON, Nov 26 (Reuters) - European shares hit fresh three-month highs on Thursday, rising in thin trade as expectations grew for aggressive European Central Bank action next week.
A solid quarterly report from chipmaker Infineon and a rebound in metal prices also provided support.
The pan-European FTSEurofirst 300 index was up 0.9 percent at 1,515.25 points, hitting its highest level since August.
However, the index's rise came in low volumes, trading just 40 percent of its 90-day average amount with little under an hour to go in the session. Wall Street was closed for the U.S. Thanksgiving holiday.
The euro edged towards seven-month lows against the dollar as investors bet that the ECB would ease policy again in December.
"Expectations surrounding the ECB are running very high and this is driving European markets higher, weakening the euro and helping them do better than U.S. stocks," said Marco Vailati, head of research and investment at Italy's Cassa Lombarda.
"I think and hope the ECB will not disappoint but I realise that it won't be that easy."
Infineon climbed 12.5 percent after the chip maker posted quarterly operating results that were higher than expected and promised an increase in revenue for its latest financial year at the high end of analysts' expectations.
"Infineon has proven surprisingly resilient and is executing very well," said Bernd Laux, an analyst at Kepler Cheuvreux, keeping his "hold" recommendation. "Based on its new guidance, the shares are not expensive any more."
The company also proposes a dividend increase to 0.20 euro a share, also higher than expected.
The bullish update boosted other chipmakers, with STMicro up 5.7 percent and Dialog Semiconductor up 3.9 percent.
Remy Cointreau fell 3.5 percent after reporting a 7.3 pct fall in like-for-like current operating profit in the first half, reflecting soft Chinese demand for its premium cognac.
Another drinks company, Royal UNIBREW, rose 8.4 percent after reporting quarterly results above analysts' expectations and raising its medium-term core profit target.
Abengoa shares slumped for a second day as the renewable-energy firm continued insolvency proceedings. A potential investor backed out of a 350 million-euro deal to recapitalise the company. The stock was down 30 percent, after wiping out half its market value on Wednesday.
Mining stocks were among the top gainers, rising 1 percent, as base metals prices rallied after falling to multi-year lows early in the week.
Auto stocks were also in demand, with the sector index up 2.4 percent, benefiting from weakness in the euro.
The sector was also helped by gains in Volkswagen, which rose 3.5 percent and is set for a 10th straight day of gains.
Baader Bank Helvea confirmed its "hold" rating on the stock and said it remained cautious, because of uncertain costs related VW's rigging emissions tests for some of its cars.
Europe bourses in 2015: link.reuters.com/pap87v
Asset performance in 2015: link.reuters.com/gap87v
Today's European research round-up RCH/EUROPE (Reporting by Danilo Masoni; Editing by Alison Williams)