LONDON (Reuters) - Britain's leading share index edged lower on Friday as strength in banks and energy firms was not enough to offset a drop in retailers, which fell back as concern over competition from Amazon (>> Amazon.com) reared its head again.

Britain's FTSE 100 <.FTSE> ended the week 0.1 percent lower at 7,401.46 points as sterling rose towards the end of the session, but the blue chips still posted a 1.1 percent gain and was on course for a 1.1 percent gain on the week.

Subprime lender Provident Financial (>> Provident Financial) jumped 22.5 percent, recovering some of the heavy losses sustained on Tuesday after its second profit warning in as many months.

The company said on Friday it was reorganising its beleaguered home credit business, replacing its head with immediate effect. Provident shares were still down 50 percent on the week.

Energy stocks and financials combined added 7 points to the index, while miners Rio Tinto (>> Rio Tinto), BHP Billiton (>> BHP Billiton Plc) and Anglo American (>> Anglo American) cemented gains as copper prices hit a three-year high on a brightening outlook for demand from China.

Cyclical sectors such as miners, which benefit from their high dollar exposure in a weaker sterling environment, have been supporting benchmarks and the FTSE 350 mining index <.FTNMX1770> hit its highest in three years on Friday.

Retailers, however, limited index gains after Amazon said it would cut prices at Whole Foods Market (>> Whole Foods Market, Inc.), the food chain it acquired in June, reigniting fears of aggressive price competition for Europe's supermarkets.

Supermarket chains Tesco (>> Tesco), Morrisons (>> Wm Morrison Supermarkets), Marks & Spencer (>> Marks & Spencer Group) and Sainsbury's (>> J Sainsbury) were among top fallers, down by 0.4-1.7 percent and tracking a broader slide in European retail stocks.

With the earnings season coming to a close, analysts said that British companies' performance had been solid.

"Numbers have been pretty good in August, having had a couple of soft months in June and July," said Ian Williams, Peel Hunt strategist, adding that there were more upgrades than downgrades in analysts' earnings revisions.

Drugmaker Shire (>> Shire) was also among the biggest gainers, rising 1.5 percent after Kepler Cheuvreux gave the stock a "buy" rating.

Among mid-caps, Computacenter (>> Computacenter plc) jumped 15.6 percent and posted its best day in more than eight years as investors cheered half-year results that showed revenue growth and increased shareholder returns.

(Reporting by Helen Reid and Kit Rees; Editing by Matthew Mpoke Bigg)

By Helen Reid and Kit Rees