Tens of thousands of extra school places will be needed by next year amid a continuing surge in demand, the Nation Audit Office said.
Ministers will visit schools in London today to see the problem for themselves.
According to Barking Council, an estimated 1,000 extra primary school places will be needed in Barking each year, in line with projected population growth.
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Cold and sunny for most, increasingly cloudy from the west. Cloud and wind spreading from the west of UK.