Why is blue colour associated with Dalit identity?

Rahul Gandhi wore blue T-shirt to Parliament to express support for BR Ambedkar, an advocate of Dalit community. Dalit activist SR Darapuri said besides being Ambedkar's favourite colour, blue was also the colour of flag of the party floated by Ambedkar, All India Scheduled Castes Federation in 1942. Political parties like BSP also embraced blue as part of its branding.