AUSTRALIAN voters rejecting a constitutional referendum was a “shameful act,” indigenous campaigners said on Sunday.

Many supporters of the Indigenous Voice to Parliament proposal maintained a week of silence and flew Aboriginal flags at half-mast across Australia after the October 14 vote decided against enshrining such a representative committee in the constitution.

In an open letter to federal lawmakers on Sunday, Yes campaigners said the result was “so appalling and mean-spirited as to be utterly unbelievable.”

“The truth is that the majority of Australians have committed a shameful act, whether knowingly or not,” the letter said.

The unsigned letter said it was written by Indigenous leaders, community members and organisations.

The writers accused the conservative Liberal Party and National party of choosing to impose “wanton political damage” on the Labour government instead of supporting disadvantaged Indigenous people.

Senior Liberal senator Michaelia Cash said: “Australians on referendum day, they did not vote No to uniting Indigenous people, they did not vote No to better outcomes for our most disadvantaged. 

“What Australians voted No to was Mr Albanese.” 

The letter says that social and mainstream media “unleashed a tsunami of racism against our people” during the referendum campaign.

The referendum was defeated with 61 per cent of Australians voting No.