Mr Trump said during his campaign he would pull out of the Paris climate accord although reports indicate he has softened his approach.
In a speech this morning in Suva, Fiji's Prime Minister Frank Bainimarama said without America the battle against climate change is doomed.
He told diplomats, NGOs and government officials Mr Trump must be persuaded to change his mind.
He said if the US does withdraw from the agreement there is no hope for the world to comprehensively tackle the issue.
Mr Bainimarama said he hoped the president-elect would take up his invitation to visit Fiji and see the effects of climate change for himself.
He said he would not be muzzled by diplomatic niceties as president of next year's climate change talks in Bonn.
He said he wanted to work with Mr Trump on climate change in an atmosphere of friendly cooperation.
Mr Bainimarama appealed to the diplomats for their government's help and said a dedicated secretariat would be set up in Fiji to prepare for COP23.