"Both treat Indians as insignificant. Both are virtually a lame duck vis-à-vis Indian issues," said the Hindraf leader and former Internal Security Act detainee.
He said Pakatan state governments could have resolved half of the Indian problems by allocating lands for Tamil schools, Indian settlements, Hindu crematoriums and temples.
He brushed aside arguments by Pakatan leaders that the state governments were new to administrative politics, alleging that "they were quick to demolish Indian establishments, settlements and structures within a short period, but slow in fixing them."
Citing the Kampung Buah Pala fiaso in Penang as one of the examples, Uthayakumar said although PKR and PAS were not directly involved, "both parties watched silently while the DAP government executed the village's destruction."
He said the argument that Pakatan was new to administration does not hold water since the coalition, when ruling Perak, was quick to set aside land for Orang Asli, Malays and Chinese for their settlements, farms, temples and schools.
"But none for the Indians," he said, adding that the Kedah, Selangor and Penang governments practiced the same policies.
Inspired by Hindraf, Uthayakumar said Indians voted for change in the last general election hoping that Pakatan would provide the change they desired to end their predicament.
However, he said Indians felt shortchanged now, thus Hindraf had been put in a quandary because the community was now questioning the movement's strong electoral backing for Pakatan last year.
Uthayakumar said this was reason why his party has called on Indian voters in Bagan Pinang to boycott the by-election on Oct 11.
The by-election would see a straight fight between the BN's Mohd Isa Abdul Samad, who is also former Negeri Sembilan menteri besar, and Zulkefly Mohamad Omar, the Negeri Sembilan PAS commissioner.
Uthayakumar said HRP and Hindraf would never back the Umno-dominated BN but felt obliged to call on Indians not to vote for Pakatan as well.
"We want to send a message to both blocks that they cannot take Indian voters for granted - wooing therm during elections but abandoning them after that.
"We will explain our stand to the Indian voters in Bagan Pinang. It's up to them to accept or reject our arguments," he added.