BMW has announced that it will shut down its Cowley Mini plant for almost a month, thanks to the credit crunch.

Car production lines at the German-owned factory will shut down on Sunday, December 7, and then not reopen until Monday, January 5. This is 11 days longer than previously announced last month.

And dates have also been made public for a weekend shutdown revealed in The Oxford Times last month. The plant will close from November 21-23.

But bosses have brought forward part of an annual bonus windfall, normally paid in January. Workers will now receive a £400 cash payment in December to help offset the cost of Christmas.

The announcement of the prolonged break follows BMW Group’s 2008 results for the third quarter. These show that pre-tax profits for the Munich-based multi-national car producer have tumbled 63.5 per cent, from £616.1m in July, August and September last year, to £224.7m in the same three months this year.

Oliver Zipse, managing director of the Mini plant, said: “Mini continues to weather the current economic conditions reasonably well.

“Worldwide sales are currently 12.1 per cent up this year and production remains at about the same level as last year.

“Due to our flexible working time arrangements with working time accounts, our associates will receive their basic pay during this period. Also, in recognition of their hard work during this challenging year, we have decided to bring forward a part payment of the annual bonus.”

BMW spokesman Angela Stangroom said: “Mini figures show that for the three months July-September, we actually sold more Minis than last year — up 1.4 per cent from 57,315 to 58,105.

“And the fact that production is at about the same level as last year is indicative of the strength of the brand.”

She added that workers would have to pay back the hours they owe the company during the New Year but there were no plans for any job losses.

Bernard Moss, union convenor at the plant, said: “Everyone was expecting an announcement like this, so I think most people are simply relieved to know where they stand now in the run-up to Christmas.”

He added: “So far, there are no shift changes planned. But things can change from week to week.

“It’s just fingers crossed for the New Year now — though, to be honest, I would be quite pleased if production figures next year were similar to this year’s.”

For the first nine months of this year, Mini production was up 12.1 per cent, from 164,891 in 2007 to 184,915. BMW Group sales were also up at £32.63bn compared to £32.62bn in 2007. Management expect the Cowley plant to produce about 237,000 cars this year — the same as last year.