Sounds like a fault with your airbag/seatbelt system to me. You'll have to find someone with the diagnostics equipment to wire your car up to a PC to fully diagnose the problem and clear the errors stored in your ECU, and the obvious choice would be a Renault dealer, but you could try other local garages. It'll probably be something simple anyhow, but I personally wouldn't ignore it - afaik, while those lights are on, your airbag systems won't work!