  We study the high-energy small-angle {\it Regge} limit of the
fermion-antifermion scattering in gauge theories and consider the part of the
amplitude suppressed by a power of the scattering angle. For abelian gauge
group all-order resummation of the double-logarithmic radiative corrections to
the leading power-suppressed term is performed. We find that when the logarithm
of the scattering angle is comparable to the inverse gauge coupling constant
the asymptotic double-logarithmic enhancement overcomes the power suppression,
a formally subleading term becomes dominant, and the small-angle expansion
breaks down. For the nonabelian gauge group we show that in the color-singlet
channel for sufficiently small scattering angles the power-suppressed
contribution becomes comparable to the one of BFKL pomeron. Possible role of
the subleading-power effects for the solution of the unitarity problem of
perturbative Regge analysis in QED and QCD is discussed. An intriguing relation
between the asymptotic behavior of the power-suppressed amplitudes in Regge and
Sudakov limits is discovered.
