Cameron challenged on per pupil spending promise
David Cameron has admitted that the amount spent on each pupil in schools in England will not keep pace with inflation, if the Conservatives are in government after the next election.
The prime minister's admission came as he unveiled a Tory manifesto promising to protect school spending.
Labour said he had "let the cat out of the bag" while the Liberal Democrats described it as a "real-terms squeeze".
Nick Robinson reports.