Guillermo del Toro has won the best director prize at the 90th Academy Awards for The Shape of Water, defeating film-makers such as Paul Thomas Anderson (for Phantom Thread), Greta Gerwig (for Lady Bird) and Jordan Peele (for Get Out).

In his acceptance speech, del Toro said: “I am an immigrant ... The best thing our industry does is to help erase the lines in the sand when the world tries to make them deeper.”

This was Del Toro’s first nomination as director (and one of 13 for The Shape of Water, the most of any film this year) and he becomes the third Mexican film-maker in the last five years to win best director, after Alfonso Cuarón for Gravity in 2014 and Alejandro González Iñárritu for Birdman and The Revenant in 2015 and 2016 respectively.

The Shape of Water stars Sally Hawkins as a mute cleaner working in a cold war-era lab facility, who bonds with a sea creature being kept there. Del Toro was the strong favourite in this category having taken a string of major awards this year, including best director at the Golden Globes and Baftas, as well as winning the Directors Guild award, a key bellwether.

However, shortly before the Academy Awards, the family of playwright Paul Zindel launched legal action over “glaring similarities” between The Shape of Water and Zindel’s 1969 play Let Me Hear You Whisper. The film’s studio Fox Searchlight have denied the allegations.