A confidential survey by the social affairs ministry found that 21% of the Dutch back changing the appearance of Sinterklaas’s controversial helper Zwarte Piet.

The report, which was for internal use only, has been leaked to television programme Medialogic.

The ministry report shows a steady rise in approval for altering the character’s appearance – currently typified by blackface make-up and a curly black wig.  In 2014, 12% of the population backed change and this rose to 17% last year. Now one in five people support a different approach.

Of the native Dutch, 18% now support change, compared with 43% of people with an Antillean or Surinamese background, the report said.

Last month, broadcaster RTL said it would only feature Piets with sooty flecks on their faces, to reflect the story that Piet brings presents down the chimney.