Average class sizes have risen in 474 out of 533 constituencies in England since 2010, according to analysis by the NEU teaching union published today.

The analysis highlights 20 areas where the average primary class contains at least 28.8 pupils:

The areas listed above all have an average class size of 28.8 or more. Across Europe, the average primary school has 20 pupils per class, the analysis notes.

Read: Class sizes bigger in '9 out of 10 areas' since 2010

Revealed: The 20 areas with the smallest class sizes

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Class sizes in the spotlight

The NEU has also named the 20 constituencies with the highest average secondary class sizes:

All those listed above have at least 23.9 pupils per class on average, against a European average for "lower secondary" of 21 pupils.