  Self-compression of multi-millijoule femtosecond laser pulses and dramatic
increase of the peak intensity are found in pressurized helium and neon within
a range of intensity in which the ionization modification of the material
parameters by the pulse is negligible. The pulse propagation is studied by the
(3+1)-dimensional nonlinear Schroedinger equation including basic lowest order
optical processes -- diffraction, group velocity dispersion of second order,
and Kerr nonlinearity of third order. Smooth and well controllable pulse
propagation dynamics is found. Constructing of compressed pulse of controllable
parameters at given space target point can be achieved by a proper chose of the
pulse energy and/or gas pressure.
