European shares fall, Greek weekend debt talks prompt caution
* FTSEurofirst 300 down 0.2 pct, Euro STOXX 50 flat
* Volatility rises, protection sought ahead of Greek talks
* K+S surges after Potash offer, supports DAX
* Tesco top FTSEurofirst gainer after sales beat forecasts (Updates prices)
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 0.2 percent at 1,569.71 points at 1209 GMT. The euro zone's Euro STOXX 50 was flat, while Greek shares fell 0.5 percent.
The VSTOXX, a volatility measure that is a crude measure of investor fear, also rose. Continuación...