  Since the launch of INTEGRAL in late 2002 we have monitored the Galactic
microquasar GRS 1915+105 with long exposures (~100 ks) pointings. All the
observations have been conducted simultaneously with other instruments, in
particular RXTE and the Ryle Telescope, and in some cases with others (Spitzer,
Nancay, GMRT, Suzaku,...). We report here the results of 3 observations
performed simultaneously with INTEGRAL, RXTE, the Ryle and Nancay radio
telescopes. These observations show the so-called $\nu$ and $\lambda$ classes
of variability during which a high level of correlated X-ray and radio
variability is observed. We study the connection between the accretion
processes seen in the X-ray behaviour, and the ejections seen in radio. By
observing ejection during class $\lambda$, we generalise the fact that the
discrete ejections in GRS 1915+105 occur after sequences of X-ray hard
dips/soft spikes, and identify the most likely trigger of the ejection through
a spectral approach to our INTEGRAL data. We show that each ejection is very
probably the result of the ejection of a Comptonising medium responsible for
the hard X-ray emission seen above 15 keV with INTEGRAL. We study the rapid
variability of the source, an find that the Low Frequency Quasi-Periodic
Oscillations are present during the X-ray dips and show variable frequency. The
ubiquity of this behaviour, and the following ejection may suggest a link
between the QPO and the mechanism responsible for the ejection
