(Updates to closing prices)

* FTSE 100 own 0.1%, FTSE 250 rises 0.1%

* Balfour Beatty jumps after raising annual operating profit

forecast

Aug 12 (Reuters) - London's FTSE 100 closed lower on

Wednesday for the third straight day, as investors cautiously

monitored efforts to end the war in the Middle East, while

Balfour Beatty soared to a record high after raising its annual

forecast.

The blue-chip FTSE 100 index closed 0.1% down at

10,833.15 points. The midcap FTSE 250 ticked up 0.1% to

24,814.88 points.

* U.S. consumer prices barely increased in July as the cost

of gasoline declined for a second straight month, while

underlying inflation was benign, further reducing the odds of an

interest rate hike from the Federal Reserve next month.

* Oil prices fell in volatile trading, having earlier traded

$1 higher, after forecasters cut projections for 2026 global oil

demand, while attacks on ships in the Middle East continued as

talks to end the Iran war hit an impasse.

* Shares of precious metal miners Fresnillo and

Endeavour Mining ( EDVMF ) firmed, tracking higher gold prices

after data showed U.S. inflation rose in line with expectations,

bolstering bets that the Federal Reserve will keep rates on hold

in September.

* Investors are also waiting for the UK's GDP data on

Thursday, which is expected to show economic growth stalled on a

month-over-month basis in June following a 0.1% growth in May.

* Britain's new Prime Minister Andy Burnham said in an

interview with the BBC that his government will do what it can

to help lower costs for business, though he acknowledged a

"difficult financial outlook". Traders are currently pricing in

a 46% chance of a 25-basis-point rate hike by the Bank of

England in December.

* Among the midcap index, Balfour Beatty jumped 7%

after the construction group raised its annual operating profit

forecast, while Hill & Smith ( HSHPF ) slid 4.9% after the

infrastructure supplier expected underlying operating profits

modestly ahead of previous guidance.

* Ocado ( OCDGF ) jumped 15.6% after J.P.Morgan said it

additional customer wins are achievable for the online grocery

group.