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May 18 (Reuters) - Santos STO.AX, Australia's no.2 oil and gas producer, said on Monday it had achieved first oil from the first phase of its Pikka development project in the U.S. state of Alaska.

The project is expected to reach a gross production plateau of 80,000 barrels of oil per day during the third quarter of fiscal 2026, with first sales revenue expected around two to three months following first oil, the company said.

Santos is the operator of the Pikka project and holds a 51% stake, while its partner Repsol REP.MC owns the remaining 49%.

Last month, the Adelaide-headquartered firm retained its annual production and sales forecasts despite a temporary outage at a gas facility and weather-linked disruptions impacting its first-quarter output.