He warned during last week's World Environment Day, hosted in the New Zealand capital, Wellington, that parts of his island nation were already underwater, forcing some of Kiribati's 94,000 people living in shoreline village communities to be relocated from century-old sites.
Tong said that worst-case scenarios show Kiribati will be submerged within a century. He told The Associated Press last week that all 94,000 Kiribati residents eventually will have to be relocated, probably within 60 years.
He hopes that nations will open their doors, not to refugees, but to "skilled immigrants" from his country, he told the AP. On Monday, he called on partner nations to accept the people of Kiribati "because we will need to relocate our people at some time in the future."
Kiribati is made up of 33 islands, 21 of them inhabited. Many are low-lying and have been identified as being at risk from rising sea levels. Tong said last week the highest point on most islands is just two yards above sea level.
Under a bilateral agreement signed Monday, New Zealand doubled its aid commitment to Kiribati over the next five years, supporting Kiribati's marine training center and helping manage the effects of climate change and rapid urbanization on the islands.
Maritime workers are responsible for 15 percent of the nation's annual gross domestic income.
Clark said her country would provide $25 million in aid over the five years to 2013 -- up from $11 million from 2003.
After an initial slow start, Kiribati families were lining up "in large numbers" for 75 places to relocate to New Zealand each year, she said.
Hundreds more Kiribati nationals were taking part in a regional labor program, enabling Kiribati citizens to work as seasonal agricultural workers in New Zealand.