It is found that phase transitions should occur between two phases of H2O with different degrees of orientational order of dipoles in a very high local field E similar to 10(9) V m(-1) at temperatures in the range 273-303 K. Critical point of H2O at T-c(E) = 308 +/- 5 K is pre dicted. The analysis is based on a rigorous equation of state. The discontinuity DeltaC(p) of the heat capacity at the transition is calculated. A consistency of the present results with a laser temperature jump experiment at a Hg/aqueous electrolyte interface is discussed. (C) 2004 Elsevier B.V. All rights reserved.