France, May 20 -- The French government "at the highest level" covered up a scandal over the treatment of mineral water by food giant Nestle, including the iconic Perrier brand, an investigation by France's upper house of parliament said Monday.

In recent years the Swiss food and drinks conglomerate has been under pressure over its Perrier and other brands as EU regulations strictly limit what treatments are allowed for any product marketed as natural mineral water.

"In addition to Nestle Waters' lack of transparency, it is important to highlight the state's lack of transparency, both towards local and European authorities and towards the French people," said the report by a commission of inquiry of the French Senate.

The report follow...