Addressing the virtual meeting on Friday, President David Kabua laid out the existential threat facing his country and the Pacific.
Kabua is the lone Pacific leader invited by US President Joe Biden to the two-day talks.
Kabua shared the stage with the world's biggest economies and pressured those he said held the Pacific's future in their hands.
President Kabua said there were a series of island nations already feeling the effects of rising oceans.
He said the Pacific now faced an even greater threat.
"We are low-lying atoll nations, barely a metre above sea level," he said.
"For millennia, our people have navigated between our islands to build thriving communities and cultures.
"Today, we are navigating through the storm of climate change, determined to do our part to steer the world to safety."
Kabua told the leaders their actions had a direct bearing upon the future of the Marshall Islands and others in the Pacific and beyond.
He called for stronger emission targets, a carbon levy to help the most vulnerable and for 50 percent of climate financing to go towards adapting to the devastating effects of climate change.
"We know what a safe harbour looks like."
Kabua said the Marshall Islands, with AOSIS, fought for years to create consensus around a 1.5 degrees Celsius temperature goal.
"In 2015, we brought together the High Ambition Coalition to turn the 1.5 to stay alive rallying cry into a goal shared by all parties to the Paris Agreement."
The role of the coalition is even more important today to ensure that 1.5 remains in reach, Kabua said.
He said the coalition's key task this year was to ensure that updated national emissions commitments were in line with that goal.
"NCDs are where ambition moves from promise to plan. Given how far off-track the world is today, it is vital that we come together every five years to increase ambition.
"All nations should also be charting long-term net zero strategies and implementation pathways before COP26 in the UK in November."
Too often, vulnerable countries hear the excuse that steep emissions cuts are too costly, Kabua said.
But he added political signals, especially from the major economies, shaped decisions on investment and innovations for low-carbon pathways.
"Together with the Solomon Islands, we are pushing for stronger emissions action at the IMO through a carbon levy to fund research and help the most vulnerable.
"Leading from the front-lines, we were the first to strengthen our NDCs in 2018. And we have a 2050 net-zero strategy paired with an electricity roadmap as our implementation pathway.
"We recently celebrated the success of the Micronesia Challenge and will be joining the Local2030 Islands Network."
But the President said all this would not be enough if the big emitters failed to act.
We feel the effects of climate change now, he said, and so the Marshalls is leading the way on adaptation.
Kabua said Majuro delivered its Adaptation Communication in 2020 and developing the National Adaptation Plan.
"Adequate and accessible financing is key. And so I support the call for 50 percent of climate financing to go towards adaptation." ■