* Strong U.S corporate results, factory survey add support

* Energy firms and banks advance

By Harpreet Bhal

LONDON, July 15 (Reuters) - Strong U.S. corporate results
and improving U.S. economic data lifted Britain's top share
index by 2.6 percent to its highest close in four weeks on
Wednesday.

Led by energy firms and banks, the FTSE 100 index .FTSE
ended up 108.78 points at 4,346.46, its third day of gains.

The UK benchmark is up 5.3 percent this week, on track for
its best weekly gain in two months.

Chip maker Intel Corp (INTC.O: Quote, Profile, Research) maintained the positive tone
of U.S. second-quarter earnings with better-than-expected
results, following upbeat figures from Goldman Sachs (GS.N: Quote, Profile, Research).

The market was also buoyed by a key regional U.S. factory
survey which posted its strongest reading in a year this month
and data showing U.S industrial output declining at a slower
pace in June. [ID:nN15329440]

Analysts said market direction will likely be dictated by a
slew of corporate earnings from the United States this week.

"We have got a number of global giants still to report later
this week and the balance of the second quarter results still
remains very important," said Keith Bowman, analyst at
Hargreaves Lansdown.

Energy firms added the most points to the UK index as crude
oil rose to $60.85 CLc1 after data showed a fall in gasoline
stocks.

Tullow Oil (TLW.L: Quote, Profile, Research) topped the energy stock risers, up 5.1
percent as it announced its Jubilee field phase 1 development
plan had been formally approved by the minister of energy in
Ghana.

Cairn Energy (CNE.L: Quote, Profile, Research), Royal Dutch Shell (RDSa.L: Quote, Profile, Research), BP (BP.L: Quote, Profile, Research)
and BG Group (BG.L: Quote, Profile, Research) gained between 2.3 and 3.1 percent.

The FTSE 100 has clawed back almost 26 percent from an
all-time low hit on March 9 but is down 2 percent for the year.

Banks were also in positive territory on Wednesday, led by a
4.8 percent gain in Barclays (BARC.L: Quote, Profile, Research). The bank is considering
the sale of its private equity business and will meet investment
partners this week to discuss the issue, several people familiar
with the matter said. [ID:nLF333303]

HSBC (HSBA.L: Quote, Profile, Research), Lloyds Banking Group (LLOY.L: Quote, Profile, Research), Royal Bank of
Scotland (RBS.L: Quote, Profile, Research) and Standard Chartered (STAN.L: Quote, Profile, Research) added between
1.5 and 4 percent.

Higher metals prices lifted mining firms with Fresnillo
(FRES.L: Quote, Profile, Research), Kazakhmys (KAZ.L: Quote, Profile, Research), Eurasian Natural Resources
(ENRC.L: Quote, Profile, Research), Lonmin (LMI.L: Quote, Profile, Research) and Xstrata (XTA.L: Quote, Profile, Research) rising between 2.6
and 5.6 percent.

Rio Tinto (RIO.L: Quote, Profile, Research) gained 4.2 percent after the company said
iron ore output in the second quarter was up 8 percent on a year
earlier.

UNEMPLOYMENT RISES

British unemployment hit its highest rate since January 2007
in the three months to May, although the number of people
claiming jobless benefit rose by much less than expected last
month, the Office of National Statistics said. [ID:nLF150992]

On a more positive note for the UK economy, Land Securities
(LAND.L: Quote, Profile, Research), the UK real estate company, said it was preparing for
new buys in the battered UK commercial property market. It added
4.5 percent.

RSA Insurance (RSA.L: Quote, Profile, Research) was up 2.1 percent, with traders
citing talk of bid interest from Generali (GASI.MI: Quote, Profile, Research).

Prudential (PRU.L: Quote, Profile, Research), Aviva (AV.L: Quote, Profile, Research), Legal & General (LGEN.L: Quote, Profile, Research)
and Old Mutual (OML.L: Quote, Profile, Research) gained between 5.3 and 7.4 percent.

ICAP (IAP.L: Quote, Profile, Research), the world's largest interdealer broker, was
one of only two stocks in the red, down 2.9 percent after going
ex-dividend. Falls were tempered, however, as it posted a 10
percent rise in revenue for the period between April and June.

Reckitt Benckiser (RB.L: Quote, Profile, Research) was another loser, off 0.3 percent.
(Editing by David Cowell)