UK GAS-Norwegian supply, new LNG and weak signals push prices lower

* Gas network undersupplied

* Norway's Troll field resumption reassures traders

* New LNG, milder weather and currencies force down prices

April 28 (Reuters) - British natural gas prices fell on Tuesday as milder weather expectations, higher Norwegian production and new seaborne supply outweighed any bullish impact from an undersupplied network.

Prices for within-day delivery were at 45 pence per therm at 0850 GMT, down 0.3 pence since their last settlement. Prices for delivery on Wednesday were down 0.37 pence at 44.85 pence per therm.

With supply flows at about 215.4 million cubic metres (mcm) per day on Tuesday and demand expected to be about 227.2 mcm, the system was 12 mcm undersupplied, National Grid (LSE: NG.L - news) data showed.

"The tightness was expected, what people are looking at is weather getting warmer and the potential for more gas," a trading analyst at a major utility said.

One trader said that prompt losses had been led by selling of the third-quarter UK gas contract, down 0.2 pence at 42.65 pence per therm amid expectation of cheaper and more plentiful oil-indexed gas arriving via links from mainland Europe.

"A glut of oil-indexed gas (from Russia and North Africa) due to come into Europe is dragging down Q3," the trader said, pointing to a discount of more than 2 pence per therm on UK gas for third-quarter delivery compared with spot prices.

Oil-indexed gas from Russia and Algeria will get cheaper this year once lower oil prices fully work through into gas contracts.

Brent crude oil prices were also trading down on Tuesday.

"Even (Taiwan OTC: 6436.TWO - news) reference markets such as Spain are trading in line with the (Dutch gas trading hub) TTF on the spot, which means Spain is not consuming much French gas, contributing to a glut in northwest European markets," the trading analyst said.

French gas markets link up with Dutch, Belgian and eventually British hubs. Spain has limited pipeline connections with France.

Norway's biggest gas field, Troll, is expected to boost supplies heading to Britain via the Langeled pipeline on Wednesday, analysts at Thomson Reuters Point Carbon said.

Deliveries from the field are now being ramped up after a gas outage that had restricted output since April 10.

Two new LNG tankers were added to the arrivals list for northwest Europe.

Further along the curve, gas for May delivery was 0.25 pence lower at 43.6 pence per therm.

In the Netherlands, the day-ahead gas price at the TTF hub was 0.40 euros lower at 21.30 euros per megawatt-hour (MWh).

The benchmark European Union carbon price edged 0.02 euros higher to 7.21 euros a tonne on ICE Futures Europe. (Reporting by Oleg Vukmanovic in Milan; Editing by David Goodman)