The current trend among environmentalist to be for "no growth" equally across the board around the world is actually detrimental to both their cause and to fiscal accountability. The reality is third and second world countries, the poor of the Earth, need to be allowed a level of growth to escape the poverty their countries are so trapped in.
No, a no-growth policy does not undermine fiscal accountability in the UN, because sticking to a budget does just the opposite. A person who has to stick to a budget, without increasing spending, is a person who is accountable to the details of that budget. Countries are not accountable when they overspend what is reasonable.