"It is with great concern and deep anguish that I am writing to you once again on the disturbing issue of unauthorised construction of barrages by the upper riparian states, which are dishonestly appropriating waters that are rightfully allocated to Andhra Pradesh," Naidu said in a letter to Manmohan Singh [Images].

"We have been consistently, persistently and repeatedly requesting, arguing and peacefully raising the issue with grave concern at various forums to get the illegal constructions stopped," he said.

The sensitive issue of illegal utilisation of both Godavari and Krishna waters by Maharashtra and Karnataka, with utter disregard to the awards passed by different Tribunals, was a glaring act of violation of law, he said demanding immediate intervention of Centre to avert deepening of inter-state water disputes.

The Babhali project being built by Maharashtra on river Godavari alone would deprive AP of 65 tmc ft of water and leave the Sriram Sagar project area in Telangana region totally parched, Chandrababu apprehended.

In all, Maharashtra was building 13 projects illegally on Godavari, the letter says.

Referring to Krishna, the former Chief Minister pointed out that the Karnataka government was building 58 barrages, with each capable of impounding 2 tmc ft of water.

"While Maharashtra has erected gates on Babhali projects in total violation of the Supreme Court order, the projects undertaken by Karnataka are nearing completion. Being the lower riparian state, Andhra Pradesh is worst hit because of the illegal projects and has become a victim of the brazen interests of the two neighbouring states," Chandrababu noted.

He urged the Prime Minister to intervene and resolve the inter-state disputes, duly protecting the rights of respective states in the "larger interest of the country."