Antonio Guterres, the UN Secretary General is asking world leaders to bring plans, not speeches to a climate summit he is hosting in September this year.

Representatives of Antonio Guterres wrote to heads of government last week, urging them to “demonstrate a leap in collective national political ambition and massive low-emission movements in the real economy”.

Climate Home News understands organisers do not intend to give politicians the UN podium for speeches, in a departure from the typical format of such events.

“This summit will be action-oriented,” he wrote, which was shared with CHN, said. “The deliverables and initiatives that will be showcased need to be implementable, scalable and replicable and have the potential to get us in line with the commitments of the Paris Agreement.”

“I am calling on all leaders to come to New York in September with concrete, realistic plans to enhance their nationally determined contributions by 2020,” the UN chief wrote in an article for the Guardian this month.

Countries are due to update their current pledges to the Paris Agreement, known as nationally determined contributions (NDCs), by the end of next year.

At the summit, governments have been asked to either bring those plans forward early, or at a minimum show that they will be ready for 2020. They must explain how those plans, which mostly focus on the road to 2030, fit not only with Paris but also the latest science.

That means cutting global greenhouse gas emissions 45% by 2030 and heading for net-zero emissions by 2050, the letter said, citing last year’s blockbuster report from the Intergovernmental Panel on Climate Change (IPCC).

The summit seeks to close a huge gap between the goals of the Paris Agreement – to limit warming to 1.5C or below 2C – and the pledges countries have so far made to meet them. Current national commitments are projected to collectively limit warming to 3C. This would lead to global economic, environmental and social damage, according to climate scientists. Worse, most nations are off the pace to meet even these inadequate targets.

The note is the clearest indication yet of the hardline approach Guterres will take, after a speech last year indicating he would throw himself and “the entire United Nations” into the fight against climate change.

Practically, countries will be encouraged to form coalitions focused on specific aspects of the climate puzzle. For instance, they may collaborate on the best ways to use carbon pricing, green heavy industry or develop natural solutions like forest growth.