The FTSE 100 Index, Britain's benchmark stock market gauge, decreased by 0.67 percent, or 44.69 points, to 6,585.78 points on Friday.

The London stock index fell on Friday as investors were concerned about Greece's upcoming public vote on the country's creditors' bailout proposals.

The Greek July 5 referendum on the debt draft deal with creditors will go ahead as planned, Greece's highest administrative court ruled on Friday.

European Commission President Jean-Claude Juncker said Friday that the Greek government's position would be "dramatically" weakened in negotiations with creditors if Greeks voted "no" in Sunday's referendum.

Ashtead Group' share price increased by 1.42 percent, topping the gainers of the blue chips. Land Securities Group, Randgold Resources Ltd., British Land Company and Barratt Developments increased by 1.38 percent, 1.24 percent, 0.75 percent and 0.71 percent respectively.

Smiths Group led the top losers of the blue chips with a share price drop of 2.41 percent, followed by Rolls-Royce Holdings (2.28 percent), Standard Chartered (2.14 percent), Vodafone Group (2.03 percent) and Morrison Supermarkets (2.00 percent).