Ban said Modi will be addressing the General Debate of the UN General Assembly on September 27 but will not be participating in the climate change summit on September 23.

"Even though he (Modi) will not be able to participate in climate summit meeting, per se, I really wanted to have him participate in climate change summit meeting," Ban told reporters here yesterday during his briefing ahead of the start of the 69th General Assembly session.

Ban was asked to comment on the leaders of India, Russia and China not attending his summit on climate change, which said is a "defining issue of our times."

Chinese President Xi Jinping and Modi will not be attending the Secretary General’s climate change summit.

Ban said even though the leaders from India, China and Russia will not be able to participate in the meeting, there are "other means of communications, ways and means of having their leadership demonstrated in the United Nations."

India's Environment Minister Prakash Javadekar is expected to represent the country at the summit, which will focus on mobilising political will for a universal and meaningful climate agreement next year in Paris and second to generate ambitious steps to reduce greenhouse gas emissions and strengthen resilience.

The day-long climate change summit will be one the "largest and biggest" gathering of world leaders with about 120 heads of states, including US President Barack Obama to participate in the event.

Ban said it is "extremely difficult to have at one day, at one time and at one place 120 heads of states and government" and the strong participation shows the "very strong commitment" on part of leaders on climate change and other global crises.

Earlier this month, Ban's spokesperson had said that while the Chinese President and Modi will not be attending the Secretary General's climate change summit, "the important issue for us is really on the commitments that countries will bring. And the Secretary-General expects every Member State to come with strong and bold commitments on climate change."

Modi is expected to reach New York on September 26 and will address the UN General Assembly the next day, giving his first global speech to an audience of nearly 200 world leaders and foreign ministers at the annual gathering of the world body's policymaking organ.

According to the report of the Intergovernmental Panel on Climate Change, headed by Indian Nobel laureate Rajendra Pachauri, the world is presently on a path that would well exceed the two degree Celsius (3.6°F) rise in temperature limit that countries have set to ensure that the world would not suffer the worst impacts of climate change.