Translate the following English sentence to French:
"However, we hope that the Council and the Commission will be able to mobilise these governments through their endeavours and that an effective action of this kind will be instigated at the Conference scheduled for 19 and 20 May, in which both institutions are to take part."
Nous espérons cependant que le Conseil et la Commission, par leurs efforts, pourront mobiliser ces gouvernements et que la participation de ces deux institutions à la Conférence prévue les 19 et 20 mai, pourra être le début d' une action efficace en ce sens.