It is shown that a process with stationary independent increments in a
n exponential Lie group can be considered as a time-homogeneous diffus
ion with jumps. In case of nilpotent Lie groups exact formula is given
for construction. The formula involves stochastic integrals with resp
ect to the corresponding process with stationary independent (additive
) increments in the corresponding Lie algebra, and reflects the group
law.