(Reuters) - Britain's biggest underground gas storage facility, Rough, experienced an unplanned outage on Friday, operator Centrica (L:CNA) said.
The outage began at 1428 GMT but Centrica could not say when it would be resolved, according to a market note.
Centrica said the outage will reduce withdrawals from the site by around 5 million cubic metres (mcm) per day.
The facility was previously withdrawing at a rate of 42 mcm per day.
Nominated withdrawals from the facility had fallen to 34.3 mcm/day at 1400 GMT from around 43.6 mcm/day at midday.