The NMSP signed the Nationwide Ceasefire Agreement (NCA) on 15 October 2015 with several other insurgent groups and the government of Myanmar.

[3] When the State Peace and Development Council (SPDC) led by Saw Maung seized power in 1988, the MNLA was among the numerous ethnic armies that opposed his rule.

The Tatmadaw has also order the withdrawal of the MNLA from bases in Mudon, Thanbyuzayat and Kyaikmayaw townships over claims that they were beyond what was permitted in the 1995 ceasefire renewed in 2012.

On 27 November 2019, the Tatmadaw and Karen Border Guard Force troops seized MNLA bases around the Three Pagodas Pass, causing the exodus of 700 Mon refugees into Thailand.

[7]Tensions between the MNLA and Karen National Liberation Army (KNLA), the armed wing of the Karen National Union (KNU), date back to 1988 over disputes in the Tanintharyi Region, particularly over territory around the Three Pagodas Pass, which the MNLA had held in the 1980s until it was taken back by the Myanmar army in 1990.

[9] Yet fighting resumed when in September 2016, MNLA fighters began clashing with members of the KNLA in the Tanintharyi Region.

[9] Both the NMSP and the KNU were signatories of the NCA at the time of the fighting and a temporary bilateral truce was reached between the two groups on 14 March 2018.