European shares fall, Greek weekend debt talks prompt caution
* FTSEurofirst 300 down 0.6 pct, Euro STOXX 50 down 0.7 pct
* Volatility rises, protection sought ahead of Greek talks
* K+S surges after Potash offer, supports DAX
* Tesco top FTSEurofirst gainer after sales beat forecasts
By Alistair Smout
LONDON, June 26 (Reuters) - European stocks fell on Friday, with investors discouraged by a lack of progress in Greek debt crisis negotiations heading into crunch talks at the weekend.
Greece failed again to clinch a deal with its international creditors on Thursday, setting up a last-ditch effort on Saturday to avert a default next week.
The pan-European FTSEurofirst 300 index was down 0.6 percent at 1,563.40 points by 0751 GMT. The euro zone Euro STOXX 50 was down 0.7 percent, while Greek shares fell 1.4 percent.
The VSTOXX, a volatility measure that is a crude measure of investor fear, rose 1.4 points to its highest level since Monday. Continuación...