UNITED NATIONS, Sept. 23 (Xinhua) -- The United Nations (UN) Secretary-General Antonio Guterres on Monday evening said that the Climate Action Summit held at the UN headquarters has seen "clear ambition and concrete initiatives."

In his closing remarks for the one-day event, Guterres thanked the participants for "delivering" on his call to put forward concrete action toward achieving carbon neutrality by 2050.

According to the UN chief, a group of the world's largest asset-owners, responsible for directing more than 2 trillion U.S. dollars, committed to move to carbon-neutral investment portfolios by 2050.

Multilateral and national development banks have increased their pledges, he said, adding that 130 banks, one-third of the global banking sector, signed up to align their businesses with the Paris agreement objectives and the UN sustainable development goals.

In addition, the UN chief reiterated the call to guarantee the implementation of the commitment by developed countries to mobilize 100 billion dollars a year from private and public sources by 2020 for mitigation and adaptation in developing countries.

He praised the small island states' announced commitment to carbon neutrality and to move to 100 percent renewable energy by 2030.

Turning to nature-based solutions, he said over 150 of them aiming to cut carbon emissions were announced, including initiatives by way of conserving 30 percent of the land and waters by 2030, and protecting the Central African Forest and the 60 million people who depend on it.

The United Nations itself also made its commitment at the meeting. The world body's pension fund, which manages 68 billion dollars in assets, announced that it will divest from investments in publicly traded companies in the coal energy sector and will not make any new investments in it.

At a press briefing following the summit, Luis Alfonso de Alba, Guterres' special envoy for the summit, praised the leadership shown at the meeting.

While describing the results as satisfying, Alba said "much more needs to be done" and stressed the need to "follow up ... each of the commitments."

He also highlighted the importance of making the connection between these announcements with the next Conference of the Parties to the UN Framework Convention on Climate Change, which is slated for December in Santiago.

Patricia Espinosa, executive secretary of the convention, said "we see this as ... an incredible outcome," adding that the momentum is building up, the solutions are there, and the possibilities are within reach.

Some 100 government, business and civil society leaders, many of them heads of state and government, spoke at the summit.

The commitments and actions announced at the summit will be put in a summary.

The Paris Agreement, a 2015 landmark climate accord, pledges to keep global warming "well below" two degrees Celsius above pre-industrial levels and strive for a lower limit of 1.5 degrees Celsius.

In a scientific report released last year by the UN climate panel, the Intergovernmental Panel on Climate Change (IPCC), it became clear that the world should strive to limit global warming to 1.5 degrees Celsius, or below.

In line with this goal, Guterres asked leaders to come to the summit with pledges consistent with reducing greenhouse gas emissions by 45 percent by 2030 and then to net zero by 2050.

A key principle in the Paris Agreement is that nations will toughen their Nationally Determined Contributions (NDCs) every five years to ratchet up the fight against global warming.

As the first opportunity to do so will be in 2020, the UN summit is seen as a slingshot to the first five-year milestone of the Paris Agreement.