The price of natural gas in Bulgaria is expected to fall by about one-fifth from the beginning of April, reflecting a sustained decline in global oil prices, the head of the country’s energy regulator has forecast.

Bulgaria relies almost entirely on imports of Russian gas to meet its needs.

The price of oil products on international markets for a prior nine-month period is being used in the formula for setting the price of Bulgarian gas imports from Russia’s Gazprom, Ivan Ivanov, Chairman of the Energy and Water Regulatory Commission told reporters on Wednesday, according to bTV.

Ivanov also said that the expected drop in gas prices would lead to a fall in the price of heating energy in the second quarter of the year but declined to elaborate.

The regulator, known by its Bulgarian acronym KEVR, sets gas prices quarterly under proposals made by state-owned gas supplier Bulgargaz. KEVR cut gas prices for the first quarter of 2016 by 2.3% last month after slashing them by some 14% for the previous quarter.

Overall, gas prices in Bulgaria were slashed by almost a third last year, making industrial production more competitive, Ivanov said earlier.