By Carla Mozee, MarketWatch

Thorntons slumps 25% as it warns on profit

LONDON (MarketWatch) -- U.K. stocks rose Tuesday, with consumer-products heavyweight Unilever PLC gaining following the purchase of two well-known brands, but shares of BG Group PLC were on the losing end of the FTSE 100 benchmark.

The FTSE 100 rose 0.6% to 6,616.94, looking for a sixth consecutive advance.

Unilever shares rose 1.2% as the company agreed to buy the Zest and Camay soap brands from Procter & Gamble Co. (PG) for an undisclosed amount. The brands logged revenue of $225 million in the last fiscal year, said Unilever. The sale is expected to close in the first half of 2015.

But losing ground was BG Group PLC , down 2.2% after Standard & Poor's Ratings Services said it may downgrade the A- corporate credit rating of the BG Energy subsidiary oil producer.

"We could downgrade the company by one notch if we foresee a further substantial rise in debt in 2015, or if oil prices remain below our current 2015 average price assumption," S&P said in a statement late Monday.

S&P also outlined concerns about highly rated oil and gas companies including Royal Dutch Shell PLC and BP PLC . Shares of Royal Dutch were higher by 0.8% and BP rose 0.5%, as oil prices edged higher.

Outside the main index, shares in Thorntons slumped 25% as the chocolate maker warned it now expects earnings in fiscal 2015 to be below those of the previous year.

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