* Britain's gas system undersupplied by 36 mcm
* Supplies cut to St Fergus, Bacton Seal terminals
* Longer-term prices helped by stronger oil market
Sept 5 British spot gas priced jumped about 14
percent on Monday, rebounding from last week's seven-year low,
after domestic supply was hit by unplanned outages.
Gas for immediate delivery rose 3.5 pence, or
13.5 percent, to 29.50 pence per therm by 0845 GMT, while the
day-ahead contract gained 3.75 pence, or 14.7
percent, to 29.20 pence/therm.
Britain's gas market was undersupplied by 36 million cubic
metres (mcm) on Monday morning, with demand forecast to be at
225 mcm and supply at 189 mcm, National Grid data showed.
"A number of unplanned outages are supporting the prices,"
gas analysts at Thomson Reuters said.
Flows at Bacton Seal terminal fell to zero from 14 mcm/day
on Friday, while flows to St Fergus Mobil terminal were down to
8 mcm/day on Monday morning from 19 mcm/day on Friday due to
unexpected outages, the data showed.
Further out along the curve, prices were helped by crude oil
futures rising sharply amid renewed speculation that major
producers including Saudi Arabia and Russia could cooperate to
tackle weak prices by holding supply steady.
The contract for gas delivery in October was
trading at 33.35 pence/therm, 0.85 pence or 2.62 percent higher,
while the contract for next winter rose 0.9 pence,
or 2.3 percent, to 40.00 pence/therm.
Dutch day-ahead gas prices at the TTF hub rose
0.05 euro to 12.30 euros per megawatt-hour (MWh).
In the European carbon market, front-year allowances
remained unchanged to 4.08 euros a tonne.
Russian Gazprom has auctioned about 2 billion
cubic metres (bcm) of gas in Europe for the 2016-17 winter, the
company said on Monday.
(Reporting by Nerijus Adomaitis; editing by David Clarke)