UK GAS-Prompt prices rise on reduced Norwegian flows

* UK gas market oversupplied by 2 mcm

* Langeled imports at 34 mcm

Aug 6 (Reuters) - British spot gas prices rose on Thursday as imports from Norway dipped slightly and the system was close to balanced.

Prices for within-day delivery were up 0.65 pence trading at 41.55 pence per therm at 0828 GMT. The day-ahead contract traded up 1 pence at 42 pence per therm.

With supply at 171 million cubic metres (mcm) per day and demand expected to be about 169 mcm, the system was 2 mcm oversupplied, National Grid (LSE: NG.L - news) data showed.

Imports from Norway via Britain's main subsea gas import route, the Langeled pipeline, were around 34 mcm, down from around 45 mcm on Wednesday, National Grid data showed.

Total (Swiss: FP.SW - news) imports from Norway were down 3 mcm.

A planned outage at Troll, Norway's biggest gas field, is expected to cut supply by 110 mcm/day on August 7 and last until August 8, operator Gassco said.

"Planned short-term Norwegian field outage tomorrow has driven gains on the Day-ahead contract, firming by over a penny from yesterday's equivalent," said Marcel Boonaert, head of trading and portfolio at Wingas UK.

"Prices across the prompt and out to the front month are following suit, finding support from further scheduled maintenance due for the coming weeks."

Gas prices further along the curve also rose, with the Winter 2015 contract up 0.39 pence at 44.80 pence per therm.

In the Netherlands, the day-ahead gas price at the TTF hub was 0.22 euros higher at 20.50 euros per megawatt-hour (MWh).

The benchmark European Union carbon price was unchanged at 7.84 euros per tonne on ICE Futures Europe. (Reporting by Sarah McFarlane; editing by Jason Neely)