United Nations: UN Secretary-General Antonio Guterres painted a grim picture of the state of the world as leaders opened their annual meeting on Tuesday, spotlighting the breakdown of trust around the globe and the need to counter unilateralism and reinvigorate the international cooperation that is the foundation of the United Nations.

In his opening remarks, Guterres said that it “is suffering from a bad case of ‘Trust Deficit Disorder,’” and pointed to rising polarisation and populism within nations, ebbing cooperation among them and “fragile” trust in international institutions.

“Democratic principles are under siege,” Guterres said.

The UN chief also sounded the alarm on climate change, saying the world has reached “a pivotal moment” in global warming and risks runaway climate change if leaders don’t act in the next two years.

He said world leaders aren’t doing enough to combat what he calls “a direct existential threat” that is moving faster than people are working to combat it, and called for making sure the international Paris climate change agreement is implemented.

US President Donald Trump has announced he’s withdrawing his country from the pact.

Guterres is planning a climate summit next year.

This year, 133 world leaders have signed up to attend the General Assembly session which ends on October 1, a significant increase from the 114 leaders last year. Virtually all 193 UN member nations will be represented, many of the rest by ministers.

Populist leaders attending this year’s meeting including US President Donald Trump, Poland’s President Andrzej Duda and Italy’s Premier Giuseppe Conte along with the foreign ministers of Hungary and Austria.

US Ambassador Nikki Haley told reporters last week that Trump, who champions an “America First” policy, wants to talk about “protecting US sovereignty” when he addresses the assembly shortly after Guterres.

“It is not saying multilateralism can’t work,” Haley said, “but it’s saying sovereignty is a priority over all of that, and we always have to make sure we’re doing that — and there are many countries that agree with us.”

China’s Foreign Minister Wang Yi warned at Monday’s UN “peace summit” honouring the 100th birthday of South African anti-apartheid campaigner Nelson Mandela that “unilateralism and protectionism are on the rise.”

He likely had Trump in mind since the US and China have been engaged in a trade war in recent months, with the two sides imposing higher tariffs on imports from each other.

Wang said “the UN is the symbol of multilateralism” and he urged the international community to “stand united under the umbrella of multilateralism, uphold the central role of the UN in international affairs, and provide more predictability and stability in this turbulent world.”

In speeches and close to 350 meetings on the assembly sideline, the conflicts, hotspots and issues contributing to that turbulence will be debated.

The seven-year-old conflict in Syria and the three-year war in Yemen that has sparked the world’s worst humanitarian crisis and is now seriously threatening large-scale famine are certain to be in the spotlight along with African hotspots including Libya, South Sudan, Central African Republic, Mali and Congo.

French President Emmanuel Macron is expected to be a key voice joining secretary-general Guterres in speaking out against unilateralism and populism, and supporting multilateralism as key to promoting peace.

Iran’s President Hassan Rouhani, whose country has been a target of escalating US accusations over its nuclear and missile programs and international terrorist activities, is also on Tuesday’s speakers list. Iran vehemently denies any nuclear ambitions or involvement in international terrorism.

In speeches and close to 350 meetings on the assembly sideline, the conflicts, hotspots and issues contributing to that turbulence will be debated.

The United States, which holds the rotating presidency of the UN Security Council in September, has scheduled two meetings, one chaired by Trump on Wednesday which was initially to focus on Iran but has now been broadened to the topic of “non-proliferation” of nuclear, chemical and biological weapons.

The second Thursday chaired by US Secretary of State Mike Pompeo is on North Korea, the one major issue where there is a glimmer of hope for progress. The 15 council nations have been united in imposing increasingly tough sanctions to try to rein in Pyongyang’s nuclear program. But that unity now appears to be at risk over enforcement of sanctions and the broader issues of how to achieve denuclearisation of the Korean peninsula, and when sanctions should be lifted against North Korea.