NAY PYI TAW, July 12 (Xinhua) -- The first day of the third session of Myanmar's 21st Century Panglong Peace Conference has discussed 14 subjects including political, economic, social, land and natural environment issues, Secretariat of the Union Peace Dialogue Joint Committee (UPDJC) said.

These issues were submitted for inclusion in the second part of the union agreement for peace.

The third session of the Panglong peace conference kicked off in Nay Pyi Taw early on Wednesday.

Separate individual meetings were also held among the non-ceasefire signatory Northern Alliance armed groups, State Counselor Aung San Suu Kyi and Commander-in-Chief of the Defense Services Sen-Gen Min Aung Hlaing, focusing on military affairs, the secretariat said.

The secretariat said the Kayinni National Progressive Party armed group attending the conference is in talks with the Peace Commission to sign Nationwide Ceasefire Accord (NCA).

Suu Kyi said at the opening session that the door for peace always remains open to those armed groups who have not yet joined the government's NCA to have dialogue and settle the issue.

The six-day meeting, which aims to unite all ethnic nationalities and build a democratic federal union through dialogue, is set to further discuss unfinished fundamental principles on federalism as well as the formulation of new principles for the establishment of a federal union.

The conference gathered representatives of the government, the parliament, the military, invited political parties, ethnic armed organizations and civil society.

The NCA was initiated in 2015 during the previous government which brought about the first eight signatories, followed by another two during the incumbent government.

The 21st Century Panglong Peace Conferences were held twice as a follow up in August 2016 and May 2017 respectively before the current third session took place.

The second session of the peace conference was able to incorporate a total of 37 adopted principles into a union accord in the country's peace process for the first time in Myanmar's history.