Isla, 38, was spotted with a small baby bump in London last month and the star has pulled out of Now You See Me 2 due to her pregnancy, US Weekly has reported.
"Production starts in November and she knew she wouldn't be able to do it," the insider told the magazine.
The Great Gatsby actress and Borat star have been married since 2010 and already have daughters Olive, 6, and Elula, 4.
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