Oil majors Chevron and TotalEnergies in January withdrew from Myanmar, citing worsening humanitarian conditions following last year's coup.
PTTEP said in a statement that it "recognizes that equitable access to energy is a fundamental human right that all people are entitled to".
PTTEP, a unit of state-owned energy firm PTT Pcl, said it places importance in "preventing disruption to energy demand," describing Yadana as a "pivotal source of natural gas supply to the livelihood of the people in both Myanmar and Thailand."
TotalEnergies currently holds a 31% stake in the field.
The transition will conclude on July 20, after which PTTEP said it would hold a 37.1% stake, state-run Myanma Oil and Gas Enterprise with 21.8% while a subsidiary of Chevron will hold 41.1%.
PTTEP said Yadana produces about 770 million standard cubic feet per day (mmscfd) where 220 mmscfd accounts for 50% of Myanmar's gas demand for electricity generation.
The remaining 550 mmscfd is exported to Thailand and supplies 12 power plants, accounting for about 11% of the country's gas demand.