Thomson, the Permanent Representative of Fiji elected in June as President of the UNGA's upcoming 71st session, will visit China later this week and will then travel to India.
On August 29, the President-elect will be in New Delhi where it is planned that he will meet with Modi, Swaraj and Secretary for External Relations, Sujata Mehta, a press release from the office of the President of the UN General Assembly said yesterday.
"Coming from the Asia-Pacific nation of Fiji, I am pleased to have this opportunity to visit the two biggest countries in the regional group to which I belong," Thomson said, adding that he looks forward to the "high-level" talks he will have with the Governments of China and India.
"My main interest will be to discuss how the United Nations can assist and accelerate the implementation of the 2030 Agenda for Sustainable Development," he added.
He will attend official meetings in Beijing tomorrow and is expected to meet with Chinese Premier Li Keqiang, State Councillor Yang Jiechi and Minister of Foreign Affairs Wang Yi.
Swaraj will travel to New York later next month to attend the high-level General Debate of the 71st session of the General Assembly. She will address global leaders from the iconic lectern of the General Assembly on September 26.
Modi, who had addressed the UN General Assembly sessions in 2014 and 2015, will not be attending this year's UNGA session.
Thomson's visit to India assumes significance against the backdrop of New Delhi leading efforts for early completion of the long-pending reforms of the UN Security Council.
In July, India's push to achieve urgent reforms of the 15-nation Council by this year and secure a permanent seat on the horse-shoe table had suffered a setback when the 193- member General Assembly decided to roll over discussions on reforming the world body's top organ to its 71st session.
India had been pushing for completing reforms of the UN Security Council in the 70th session of the General Assembly, which will end next month.
Thomson will preside over the 71st session, which will begin on September 13, amid expectations from a majority of member states that the UNSC reform process will accelerate and concrete results will be achieved in reforming the most powerful organ of the UN.
India along with the G4 nations had said it was "unfortunate" that momentum could not build up over UNSC reforms in the 70th session.