On the other hand, HUL, which makes Pureit brand of water purifier, hit back by saying Tata Chemicals makes "ambiguous" and "misleading" claims about its product Tata Swach.
Claiming that advertising industry watchdog ASCI has upheld its complaint against leaflets circulated by HUL, Tata Chemicals said the rival was denigrating its product.
"Violating the professional code of business, Pureit, the water purifier brand from the Hindustan Unilever, had been misleading consumers through persistent smear campaigns against competition, Tata Swach, the water purifier from the house of Tatas," the statement said.