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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A GP in Surrey has launched a petition calling for a £90m fine handed to two drugs companies, to be reinvested in the NHS and epilepsy care.
Friday evening's weather update for the east
Friday evening's weather update for the west