Saudi shares ended at a four-and-a-half month high, as gains in the food sector following a US stake purchase worth nearly $1 billion outweighed losses in petrochemical stocks on lower oil prices.

The food sector index added 2.8 per cent, days after US heavyweight Coca-Cola said it was buying a stake in unlisted Saudi beverage company Aujan Industries for $980 million.

Food group Savola jumped 4.5 per cent, helping lift the all-share index 0.2 per cent to 6,254 points, its highest close since August 3. The petrochemical index dropped 0.4 per cent.

Oil edged lower in volatile trading on Friday, posting a second consecutive weekly loss as caution about Europe's debt crisis and year-end positioning continued to spark selling into rallies.

Heavyweight Saudi Basic Industries Corp (Sabic) dropped 0.5 per cent.

Earlier in the day, the shares opened higher, helped by gains in the food sector, while banking and petrochemical stocks dip in early trade after a fall in oil prices.-Reuters