LONDON MARKETS: Petrofac Plunges Nearly 30% In London, But BT Boosted

By Carla Mozee and Sara Sjolin, MarketWatch Hargreaves Lansdown PLC fell after Citi cut it to sell

LONDON (MarketWatch) -- Shares of Petrofac were slammed in London on Monday, weighing on the benchmark FTSE 100, after the oil-services firm cut its profit outlook.

The FTSE 100 shed 0.3% to end at 6,729.79, with losses led by a 27% slide in Petrofac Ltd. . The shares logged their worst session in a year, according to FactSet data, as the company said it now expects 2014 net profit to come in at the lower end of its previous forecast of $580 million to $600 million. It also foresees 2015 net profit of around $500 million, with the outlook reflecting lower oil prices and on a shortfall in execution on a "small number" of projects.

Miners also fell after staging a solid rally on Friday, when a surprise rate cut from the People's Bank of China spurred hopes that looser monetary policy would boost demand for commodities. Tony Cross, market analyst at Trustnet Direct, said in a note on Monday that "cheaper borrowing may offer some demand stimulus, but it's a drop in the ocean against the over-supply issue that's now in play, especially for products like iron ore."

Shares of Anglo American PLC dropped 1.9%, BHP Billiton PLC (BHP) lost 2.5% and Rio Tinto PLC (RIO) gave up 2.2%.

Also ending lower, stock in Hargreaves Lansdown PLC fell 5.3% after Citigroup cut the investment manager to sell from neutral.

On a more upbeat note, shares of BT Group PLC (BT) climbed 3.7% after the firm said it's in talks to buy the U.K. mobile business O2 from Telefonica .The British telecoms company said it has received expressions of interest from O2 and another U.K. mobile network operator about possible takeover by BT, but that discussions are at a "highly preliminary stage."

Shares of Friends Life Group Ltd. rallied 5.9% after a GBP5.6 billion ($8.8 billion) buyout approach from Aviva PLC , which fell 5.5%.

London Stock Exchange Group PLC added 3.3% after Citigroup lifted the company to buy from neutral.

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