  An equation is derived for analyzing the self-action of a wave packets with
few optical cycles in multicore fibers (MCF). A new class of stable
out-of-phase spatio-temporal solitons with few cycle durations in the MCF with
cores located in a ring is found and analyzed. The stability boundary of the
obtained solutions is determined. As an example of using such solitons, we
considered the problem of their self-compression in the process of multisoliton
dynamics in the MCF. The formation of laser pulses with a duration of few
optical cycles at the output of a ten-core MCF is shown.
