I think it's multiple things. First, they don't want to piss off their allies, the UK and US, by voting against UK occupation. Second, they may themselves have

I think it's multiple things. First, they don't want to piss off their allies, the UK and US, by voting against UK occupation. Second, they may themselves have similar territorial arrangements and are concerned that this sets a precedent for use of the International Court of Justice to delegitimize such possessions.