  One of the major predictions of inflation is the existence of a stochastic
background of cosmological gravitational waves (GW). These gravitational waves
can induce significant temperature anisotropies in the Cosmic Microwave
Background (CMB) on the angular scales recently probed by the Archeops
experiment. Here, we perform a combined analysis of Archeops together with
information from other CMB experiments and/or cosmological datasets, in order
to constrain the amplitude of the GW background. We find that, for a
scale-invariant GW background, the ratio of tensor/scalar perturbations at the
CMB quadrupole is now constrained to be $r \leq 0.43$ at 95% c.l., while the
bound on the spectral index of primordial density fluctuations is
$n_S=0.97_{-0.12}^{+0.10}$. We discuss the implications for future GW
detections through CMB polarization measurements.
