  The source 4U 1702-429 (Ara X-1) is a low-mass X-ray binary system hosting a
neutron star. Albeit the source is quite bright ( $\sim10^{37}$ erg s$^{-1}$)
its broadband spectrum has never been studied. Neither dips nor eclipses have
been observed in the light curve suggesting that its inclination angle is
smaller than 60$^{\circ}$.We analysed the broadband spectrum of 4U 1702-429 in
the 0.3-60 keV energy range, using XMM-Newton and INTEGRAL data, to constrain
its Compton reflection component if it is present. After excluding the three
time intervals in which three type-I X-ray bursts occurred, we fitted the joint
XMM-Newton and INTEGRAL spectra obtained from simultaneous observations. A
broad emission line at 6.7 keV and two absorption edges at 0.87 and 8.82 keV
were detected. We found that a self-consistent reflection model fits the 0.3-60
keV spectrum well. The broadband continuum is composed of an emission component
originating from the inner region of the accretion disc, a Comptonised direct
emission coming from a corona with an electron temperature of $2.63 \pm 0.06$
keV and an optical depth $\tau=13.6 \pm 0.2$, and, finally, a reflection
component. The best-fit indicates that the broad emission line and the
absorption edge at 8.82 keV, both associated with the presence of \ion{Fe}{xxv}
ions, are produced by reflection in the region above the disc with a ionisation
parameter of $Log(\xi) \simeq 2.7$. We have inferred that the inner radius,
where the broad emission line originates, is $64^{+52}_{-15}$ km, and the inner
radius of the accretion disc is $39^{+6}_{-8}$ km. (Abridged)
