By Sara Sjolin, MarketWatch

LONDON (MarketWatch) -- U.K.'s FTSE 100 index outperformed most other European markets and rose for a fourth straight day on Friday as drug maker Shire surged more than 15% after rejecting a takeover proposal.

The benchmark index in London gained 0.3% to close at 6,825.20, ending with a 0.7% weekly advance.

Leading the pack, Shire PLC jumped 17% after the pharma firm rejected a 27.2 billion-pound ($46.35 billion) takeover bid from U.S. rival AbbVie Inc. (ABBV), citing a fundamentally undervaluation of the company. AbbVie said discussions were no longer ongoing and that there could be no certainty that any firm offer would be made.

AstraZeneca PLC (AZN) -- which recently rebuffed an acquisition bid from Pfizer Inc. (PFE) -- picked up 0.6%.

Outside the main index in London, shares of TSB Banking Group PLC soared 12% on its first trading day. The move took Lloyds Banking Group PLC (LYG) one step closer to selling off the whole TSB unit as part of a condition of its government bailout. The lender must divest its remaining shares in TSB by the end of next year.

Lloyds listed 175 million shares in TSB, or 35% of the business, raising GBP455 million and selling a bigger stake than initially planned. Lloyds shares dropped 0.9%.

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