  We discuss single-diffractive production of dijets. The cross section is
calculated within the resolved pomeron picture, for the first time in the
$k_t$-factorization approach, neglecting transverse momentum of the pomeron. We
use Kimber-Martin-Ryskin unintegrated parton (gluon, quark, antiquark)
distributions (UPDF) both in the proton as well as in the pomeron or subleading
reggeon. The UPDFs are calculated based on conventional MMHT2014nlo PDFs in the
proton and H1 collaboration diffractive PDFs used previously in the analysis of
diffractive structure function and dijets at HERA. For comparison we present
results of calculations performed within collinear-factorization approach. Our
results remaind those obtained in the NLO approach. The calculation is (must
be) supplemented by the so-called gap survival factor which may, in general,
depend on kinematical variables. We try to describe the existing data from
Tevatron and make detailed predictions for possible LHC measurements. Several
differential distributions are calculated. The $\overline{E}_T$,
$\overline{\eta}$ and $x_{\bar p}$ distributions are compared with the Tevatron
data. A reasonable agreement is obtained for the first two distributions. The
last one requires to introduce a gap survival factor which depends on
kinematical variables. We discuss how the phenomenological dependence on one
kinematical variable may influence dependence on other variables such as
${\overline E}_T$ and ${\overline \eta}$. Several distributions for the LHC are
shown.
