The project produces gas from the Giza and Fayoum fields and was developed as a deepwater, long-distance tie-back to an existing onshore plant.
The two fields are currently producing around 400 million cubic feet of gas per day (mmscfd) and is expected to ramp up to around 700mmscfd at peak.
The West Nile Delta development includes a total of five gas fields – the first stage started producing gas in 2017 from two fields, Taurus and Libra.
The third stage will develop the Raven field, with production expected in late 2019.
Bob Dudley, BP Group Chief Executive said: “With the second stage of West Nile Delta now online, BP has now safely brought 21 new upstream major projects into production over the last three years, keeping us on track to deliver 900,000 barrels of oil equivalent per day by 2021.”