(Sharecast News) - London's FTSE 100 was down 0.7% at 8,199.12 in afternoon trade on Wednesday.

Fresnillo shone as JP Morgan Cazenove sounded a confident note on the outlook for the precious metals miner and kept its rating on the shares at 'overweight'.

Shell and BP gushed higher amid speculation OPEC will maintain supply cuts at its meeting on 2 June.

Ocado was under the cosh ahead of its expected demotion from the top-flight index in next week's reshuffle.

Dan Coatsworth, investment analyst at AJ Bell, said: "Ocado is no stranger to going in and out of the FTSE 100 and once again it looks set to move down a floor to the mid-cap FTSE 250 index.

"One of the most Marmite names on the UK stock market, investors either love or hate the quasi grocery/technology group and some even change their mind on a daily or weekly basis.

"There is always a 'will it, won't it' element in trying to second guess what Ocado is doing strategically. On paper, the business model is focused on winning more grocery clients to power their online shopping warehouses, while also trying to improve the performance of a joint venture with Marks & Spencer. In reality, progress has been lumpier than gravy in a school canteen.

"Despite the share price bursting into life last week, Ocado always seems to struggle to sustain momentum and once again it is a prime candidate for demotion in the quarterly FTSE index reshuffle."

FTSE 100 - Risers

Fresnillo (FRES) 629.50p 2.52%

United Utilities Group (UU.) 997.80p 1.51%

Shell (SHEL) 2,811.00p 1.10%

BP (BP.) 492.00p 1.02%

Admiral Group (ADM) 2,715.00p 0.82%

Hikma Pharmaceuticals (HIK) 1,920.00p 0.79%

JD Sports Fashion (JD.) 129.15p 0.74%

Persimmon (PSN) 1,449.50p 0.73%

Next (NXT) 9,258.00p 0.46%

NATWEST GROUP (NWG) 310.20p 0.26%

FTSE 100 - Fallers

Ocado Group (OCDO) 384.40p -6.34%

RS Group (RS1) 725.00p -3.78%

International Consolidated Airlines Group SA (CDI) (IAG) 167.95p -3.45%

Intermediate Capital Group (ICG) 2,326.00p -2.84%

National Grid (NG.) 852.60p -2.65%

Prudential (PRU) 749.60p -2.20%

Melrose Industries (MRO) 606.80p -2.19%

Entain (ENT) 659.80p -2.11%

CRH (CDI) (CRH) 6,152.00p -2.07%

Antofagasta (ANTO) 2,268.00p -1.99%