Princess Charlene of Monaco chose a Joker-themed face mask to open Tour de France

The 107th Tour de France is only four days in, but Princess Charlene of Monaco was already wearing the yellow jersey at the starting line.

(Well... a yellow jacket, but still.)

On Saturday, the princess and her husband Prince Albert inaugurated the annual cycling race, which had been delayed by two months due to the COVID-19 pandemic.

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Monaco's princely couple were joined in Nice by the mayor of the riviera city and his wife, as well as two French ministers. The group jointly cut the ribbon to signal the Grand Départ, kicking off the first stage of the 21-day race.

Fittingly, Charlene wore a vivid shade of yellow — a nod to the Tour de France's official colour and that of its famous winner's jersey.

The leading rider in each stage of the Tour wears the yellow top, which is ultimately awarded to the winner of the race.

The princess teamed her bright leather jacket with a Batman-themed face mask, featuring the Joker's red grin and famous line "Why so serious?" from The Dark Knight.

Charlene also appears to have had a short blunt fringe recently cut into her hair.

Albert, who was diagnosed with coronavirus earlier this year, also wore a mask (though a less eye-catching version than his wife's) with his suit.

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After heralding the start of the race, the royal couple was seen enjoying the action from the sidelines, joined by MMA fighter Conor McGregor.

Albert and Charlene's Tour de France appearance comes after they spent some time in Corsica with their five-year-old twins Princess Gabriella and Prince Jacques.

The princess, a former Olympian, is currently training for a charity challenge that will see her undertake a water bike marathon from Corsica to Monaco later this month.

The couple also recently celebrated their ninth wedding anniversary.