Fewer than half of 13 and 14-year-old Scottish pupils can write well and the proportion who are functionally illiterate has more than doubled, according to official figures that laid bare the SNP’s “shameful” education record.

The Scottish Government statistics showed the proportion of youngsters in the second year of secondary school who reach the expected standard for writing fell from 64 per cent in 2012 to 49 per cent last year.

In an astonishing indictment of the Nationalists, the percentage not able to write to even the minimum set standard increased from seven per cent to 16 per cent – around one in six all S2 pupils.

Contrary to Nicola Sturgeon’s claims that progress is being made at closing the ‘attainment gap’, the figures found little evidence that the gulf in performance between wealthy and poor pupils has closed since she succeeded Alex Salmond as First Minister in 2014.

Instead it concluded that standards have declined among S2 youngsters from all backgrounds since 2012, with six out of ten children from the most deprived backgrounds failing to meet the benchmark for writing.

The study also found that the proportion of children in the final year of primary school who can write well has declined from 72 per cent to 65 per cent since 2012.