* FTSEurofirst 300 down 0.7 percent
* Barclays down as key investor effectively cuts stake
* Investors await key U.S. report
* For up-to-the-minute market news, click on
By Brian Gorman
LONDON, Oct 8 (Reuters) - European shares slipped at midday on Friday, with Barclays leading the banking sector lower as a key investor effectively further cut his stake.
Traders awaited U.S. jobs data which could indicate whether more stimulus measures would be introduced to fuel the flagging recovery.
At 1048 GMT, the FTSEurofirst 300 index of top European shares was down 0.7 percent at 1,063.49 points, though on course to end the week slightly higher.
The European benchmark is up more than 64 percent from its lifetime low of March, 2009, but has gained less than 2 percent in 2010.
"We're seeing a bit of profit-taking today after a few good days, " said Mark Bon, fund manager at Canada Life in London, adding: "Ironically", it could boost the market if labour data is weaker than expected ... It could well be that if the payroll numbers are slightly disappointing, that will encourage people to think that QE (quantitative easing) will be sooner rather than later."
AT RISK
The heavyweight banking sector was a drag on the index. Barclays fell 2.7 percent after the main Middle East investor who pumped billions of pounds into it effectively sold a chunk more shares to lift his profit on the deal to over $3 billion.
The shares were also impacted by Credit Suisse analysts saying Barclays is at risk of falling short of expectations for its investment banking income in the second half of this year and in 2011.
Others banks to fall included BNP Paribas, Banco Santander and Credit Suisse, down between 1 and 1.4 percent.
But Commerzbank was among the top gainers, up 3.1 percent after sources said the German bank would not issue new shares at current prices.
Energy shares were among the losers as crude prices gave back some recent gains, retreating from five-month highs. A weaker dollar, in anticipation of QE, had helped to boost prices. Total, BP and Royal Dutch Shell fell between 0.4 and 0.6 percent.
Swiss Actelion rose 10.7 percent, building on the previous day's gains, with traders citing further talk that Europe's largest biotech company could be an acquisition target.
But concerns that a stronger euro may weigh on the pace of Europe's economic recovery were fuelled by German exports, which fell in August for the second consecutive month, narrowing the trade balance.
Across Europe, Britain's FTSE 100, Germany's DAX and France's CAC 40 fell between 0.4 and 0.8 percent.
Bon believes the market will be higher by year-end. "The (U.S.) earnings season will be important," said Bon. "Companies have been guiding analysts up, which is always encouraging."
Aluminium group Alcoa was one of the first to report. Late on Thursday, it announced third-quarter earnings that beat analysts' expectations. (Editing by David Holmes)