By Carla Mozee, MarketWatch

LONDON (MarketWatch) -- U.K.'s benchmark stock index headed for a positive end to the week on Friday, as gains for mining firms outweighed another slump for insurers, which were hit hard by plans of an investigation by the U.K. Financial Conduct Authority into older pensions and savings plans.

The U.K.'s FTSE 100 picked up 0.5% to 6,622.39, erasing earlier losses. On the week, the benchmark flirted with a 1% gain, the weekly advance in a row.

Miners helped lift the FTSE, finding support in higher metals prices and the latest comments from Chinese Premier Li Keqiang, which some analysts interpreted as a hint of upcoming easing measures to aid the slowing economy. Li said China should pay great attention to the problems and difficulties in the economic development and shouldn't overlook "downward risks," according to state-run Xinhua News Agency.

Further easing measures from Beijing are seen as a positive for miners, because a high level of growth in China could boost the demand for natural resources. Shares of Anglo American PLC advance 2.1%, Glencore Xstrata PLC (GLCNF) gained 2.1% and BHP Billiton PLC (BHP) rose 1.4%.

Oil producers also held to higher ground, with energy issues up after oil futures (CLK4) extended their rise above $101-a-barrel level. BP PLC (BP) tacked on 0.8% and Royal Dutch Shell PLC rose 0.6%.

Insurers added pressure on the FTSE, the Financial Conduct Authority confirmed it would launch an inquiry into charges and restrictions on old policies worth billions of pounds. The review will look into the terms and conditions of policies written in the 30 years up to 2000, due to suspicion that many of them effectively discriminated against old customers, to the benefit of new ones.

Shares of Resolution Ltd. plunged 8.2%, Aviva PLC slid 5.6%, Legal & General Group PLC lost 5.2% and Standard Life PLC fell 2.4%. Also, Prudential PLC gave up 3.8%.

Insurance stocks saw heavy losses recently after U.K finance minister George Osborne, as part of his annual budget, announced plans to end a rule that required pension funds to be used to buy annuities, a key portion of business for some insurance companies.

On the economic front in the U.K. on Friday, the Office for National Statistics said gross domestic product in the U.K. in 2013 expanded by 1.7%, lower than a previous estimate of 1.8%. The growth rate of 0.7% for the fourth quarter was unrevised.

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