By Carla Mozee, MarketWatch

U.K. stocks fell on Friday, with banks in focus at the start of May trading after a ratings downgrade for Barclays PLC, and as shares of Lloyds Banking Group PLC climbed after its quarterly results.

The FTSE 100 lost 0.5% to 6,923.33. Among decliners, Barclays shares were down 0.9% after a ratings cut at Berenberg to sell from hold.

Barclays is "one of our wild cards" for this year, as it holds the potential to emerge as a long-term winner in the sector," wrote Berenberg analyst James Chappell. "Unfortunately, that change seems further away than we had hoped, as the malaise from the lackluster investment-bank strategy has worsened."

But topping the FTSE 100 was Lloyds , whose shares gained 3% after the company posted a 21% rise in underlying profit (http://www.marketwatch.com/story/lloyds-profit-falls-on-tsb-sale-cost-of-1-billion-2015-05-01) to GBP2.2 billion. However, net profit fell, with Lloyds incurring a GBP660 million loss related to the spinoff of its TSB Banking Group PLC unit.

Only the mining group was pushing higher Friday, after data showed manufacturing activity in China, a major buyer of commodities, remained in expansionary territory in April (http://www.marketwatch.com/story/china-manufacturing-activity-holds-steady-2015-04-30-214854532).

Shares of mining giant Rio Tinto PLC leapt 2.8%, and BHP Billiton PLC (BHP) stepped higher by 1.9%. Anglo American PLC gained 2.9%.

Separately, Brazilian iron-ore producer Vale (RIO) on Thursday signaled it's considering cutting output (http://www.wsj.com/articles/brazils-vale-considers-cutting-iron-ore-output-1430412392) for the raw material that's used to produce steel.

Trading volumes on the FTSE 100 are seen as likely to be lower Friday, with most of Europe celebrating a Labour Day holiday. Most major European stock exchanges are closed for trading. See: Which markets are closed for Europe's Labour Day? (http://www.marketwatch.com/story/which-markets-are-closed-for-europes-labor-day-2015-04-30)

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