Mr Tu'i'onetoa was elected by Parliament last week, following the death of 'Akilisi Pohiva.
The five year long Pohiva administration has been marked by tension between the government and the nobility, but Mr Tu'i'onetoa said he wanted to end that rift and had included three nobles in his Cabinet.
He said an attitude of forgive and forget would allow the government to better develop the country.
"Of course, we still have differences but when it's coupled with the spirit of disharmony and not one to reconcile and talk to each other, that will eventually damage the whole country.
"We need to be united, with a good spirit and then along the way we can find a better solution."