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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Wednesday morning's weather for the east of the region
Wednesday morning's weather for the west of the region
War medals belonging to the late Great Escaper Bernard Jordan will be auctioned for charity.