Uganda will commission on Tuesday the first of its four planned oil drilling rigs and start drilling the first production well, its petroleum agency said, a key milestone as the country races to meet its target of first oil output in 2025.

The East African nation discovered commercial reserves of petroleum nearly two decades ago but production has been repeatedly delayed by a lack of infrastructure like a pipeline.

“Today we mark another milestone and move a step closer to first oil with the launch of the drilling of development and production wells for the Kingfisher oil fields,” government-run Petroleum Authority of Uganda (PAU) said on Twitter.

President Yoweri Museveni is due to officiate the event.

The Kingfisher oil field is operated by China’s CNOOC, while the second Tilenga oil field is operated by France’s TotalEnergies.

The two firms co-own all of Uganda’s existing oilfields alongside the state-run Uganda National Oil Company (UNOC).

The rig due to be launched on Tuesday, will be used to drill a total of 31 wells in Kingfisher while three rigs to be deployed later in Tilenga project area will drill a total of 426 production wells, according to the Ministry of Energy and Mineral Development.

Uganda’s crude reserves are estimated at 6.5 billion barrels, of which 1.4 billion barrels are recoverable.

The country will export its crude through an electrically heated, 1443-kilomtere pipeline from the oilfields to neighbouring Tanzania’s Indian Ocean seaport of Tanga.