The boss of British Gas has apologised for the rowdy behaviour of some staff at a team briefing on the day the company put up its prices for customers.

Employees attended the four-course event at the International Conference Centre in Birmingham on Wednesday night, which went on until the early hours of Thursday.

They were entertained by comedian Jimmy Carr who reportedly quipped: "I've put up my fee by 35% - just like you."

Nearly 1,000 British Gas middle managers and sales advisors were at the ICC for the event, which was held to discuss how to justify the recent price hike.

As well as comedian Carr's appearance, the Sun reported that organisers arranged for sports presenter Steve Rider to compere the dinner and rugby star Lawrence Dallaglio gave a speech to guests.

Staff are said to have been treated to free drinks at the dinner but the mood turned sour when festivities apparently got the better of some staff.

Phil Bentley, managing director of British Gas, said he was "deeply disappointed" with their behaviour.

He said: "At such a difficult time for our customers, we need our staff to understand why energy prices are rising and what support is available to help our customers cope.

"However, we're deeply disappointed with the behaviour of a few individuals who let us and our customers down after the briefing ended, for which we sincerely apologise."

Julian Mears, media relations manager for British Gas, said he was unable to confirm that the event cost £250,000.

He said: "That is something we would have to look through."