Nov. 4 (Bloomberg) -- U.K. stocks advanced for a sixth day, led by retailers, after Marks & Spencer Group Plc reported first- half net income ahead of analysts' estimates.

BP Plc and Royal Dutch Shell Plc rallied after the price of crude oil rose and BG Group Plc, the U.K.'s third-largest natural-gas producer, said it expects oil and gas reserves to rise on discoveries in Brazil and exploration progress worldwide.

The FTSE 100 Index gained 114.54, or 2.6 percent, to 4,557.82 at 3:27 p.m. in London. The FTSE All-Share Index increased 2.9 percent and Ireland's ISEQ Index added 1.7 percent.

``M&S' numbers are a relief to investors,'' said Espen Furnes, an Oslo-based fund manager at Storebrand Asset Management, which has the equivalent of $48 billion. ``The read- across to the U.K. economy is perhaps that the slowdown isn't accelerating any more.''

M&S climbed 3.6 percent to 229.5 pence. First-half net income fell to 223.2 million pounds ($350 million), or 14.2 pence a share, in the six months ended Sept. 27, from 393.2 million pounds, or 23.2 pence, a year earlier. That beat the 211 million- pound median estimate of six analysts surveyed by Bloomberg News.

Sainsbury Plc, the third-largest U.K. food retailer, added 1.3 percent to 283.25 pence.

BP, Europe's second-largest oil company, added 2.8 percent to 522.5 pence. Shell, the biggest, increased 2.9 percent to 1,796.

Crude oil for December delivery rose $2.50, or 3.9 percent, to $66.41 a barrel at 9:25 a.m. on the New York Mercantile Exchange. Prices, which have tumbled 55 percent since reaching a record $147.27 on July 11, are down 31 percent from a year ago.

Royal Bank of Scotland Group Plc, waiting to take up the U.K.'s biggest bank bailout, lost 7.4 percent to 60.4 pence. The lender wrote down 1.4 billion pounds ($2.2 billion) of assets in the third quarter and said it may post a full-year loss.

The following stocks also gained or fell in the U.K. market. Stock symbols are in parentheses.

U.K. companies:

Balfour Beatty Plc (BBY LN) gained 23.25 pence, or 8.7 percent, to 291. Britain's biggest builder said business levels since the end of June were ``in line'' with internal targets as orders continued to increase, securing long-term income.

Croda International Plc (CRDA LN) added 15 pence, or 2.8 percent, to 543. The U.K. maker of natural-based chemicals for clients such as Procter & Gamble Co. said third-quarter profit rose 73 percent on ``strong growth'' at its personal and crop care businesses.

Parity Group Plc (PTY LN) slumped 1.25 pence, or 14 percent, to 7.75. The European provider of computer-services to cereal- maker Kelloggs Co. fell to the lowest since at least 1993 after saying ``difficult'' business conditions may continue into next year.

Prodesse Investment Ltd. (PRD LN) slid 25 pence, or 6.4 percent, to 365 pence. The U.K. closed-end fund that invests in residential mortgage-backed securities said its net asset value per share fell 12 percent in the third quarter as market conditions deteriorated.

Punch Taverns Plc (PUB LN) lost 14.25 pence, or 7.8 percent, to 169.25. The U.K.'s largest pub owner posted an annual loss as Britain's slumping economy forced the company to write down the value of its properties.

To contact the reporter on this story: Sarah Thompson in London at sthompson17@bloomberg.net.

Last Updated: November 4, 2008 10:31 EST