The PM said the he had no plans to legislate, although he hinted ministers would not stand in the way of MPs attempting to introduce a backbench Bill.
Meanwhile, Home Secretary Theresa May echoed Culture Secretary Maria Miller earlier this week in suggesting a more limited reduction to 20 weeks.
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Cloudy but clearing overnight : Sunday evening's weather for the east of the region
Sunday evening's weather forecast for the west of the region
The Common People Festival had big crowds, good weather and Fat Boy Slim to bring 12 hours of music to a finale at the end of the first day