Qatargas will stop three of the world's biggest liquefied natural gas (LNG) producing plants at different times during a rolling maintenance programme planned for this autumn, the world's largest LNG producer said.

European gas prices leapt on Friday after traders with knowledge of the situation told Reuters Qatargas trains 5, 6 and 7 would shut consecutively for around two weeks each from mid September to early November -- when heating demand from big buyers in Europe and north-east Asia climbs as temperatures fall.

Qatargas did not give exact dates or durations on Sunday for the closures of its three newest production lines -- each able to produce 7.8 million tonnes a year (mtpa) of LNG -- but said it also planned to do work on parts of the 7.8 mtpa train 4 and 3.2 mtpa train 3.

'Qatargas can confirm that the planned maintenance of its Trains 5, 6 and 7, as well as Qatargas 3 and 4 inlet receiving facilities will take place this autumn,' a spokesperson from Qatargas in a statement on Sunday.

'Qatargas operates a rolling programme of planned maintenance at its facilities.  These necessary, planned and safe shutdowns are coordinated with all parties of our operations, shipping and customers as part of our annual planning exercises. There will be no impact on our existing customer portfolio.'

On Friday, traders familiar with the plans said work at trains 5-7 was expected to last for about two weeks each, also reducing Qatari condensate production while the huge processing plants attached to Qatar's vast North Field are down. 

Qatargas did not comment on whether the inlet receiving facility work would require the complete shutdown of trains 3 or 4. Some inlet receiving systems can be bypassed so that production can be maintained, while others require a complete shutdown, an industry source said.

British benchmark front-season gas prices soared six percent on Friday on fears the maintenance could cut supply to north west European consumers already worried about Qatari LNG diversions to higher paying Japan, where gas demand has boomed since a March earthquake shut nuclear power plants.

Qatargas operates seven LNG trains with a capacity of 42 million tonnes per annum (mtpa), but has signed several deals since March to sell more LNG to new markets in addition to Japan. – Reuters