In his address Frank Bainimarama urged world leaders to strive for more than just the two degrees’ target set in Paris in 2015.
In November, Mr Bainimarama will take up the presidency COP23 UN climate change conference in Germany.
He told leaders at the General Assembly they should commit to limiting global warming to no more than 1.5 degrees celsius above pre-industrial levels.
"It may be tempting for political leaders to show that they are protecting some national industry or near term economic goal," he said.
"But at what cost? If we view this as some sort of negotiation in which each country tries to preserve its narrow national interests, we will all lose. We will be powerless to protect our own people from the consequences of climate change."