Myanmar’s Zawtika gas field will be shut down for annual maintenance for 10 days starting March 19, reducing exports to Thailand by about 580 million cubic feet per day, Thailand’s sole gas supplier PTT Pcl said.

Thailand uses natural gas for almost 70 percent of its power generation and about a fifth of its supplies are imported from Myanmar. The country is under pressure to secure long-term supply as domestic gas resources are expected to be exhausted over the next six to seven years.

To offset the drop in supply from Myanmar, PTT plans to use reserves from producers in the Gulf of Thailand and onshore fields as well as seek more LNG, PTT said in a statement without giving detail where it would source this.

PTT’s subsidiary PTT Exploration and Production Pcl , owns 80 percent of Zawtika gas field at the offshore Block M9 in the Gulf of Martaban, and Myanmar Oil and Gas Enterprise has the remaining 20 percent stake.

The Zawtika field started delivering gas in 2014.