Chloë Grace Moretz has called Justin Bieber's remarks about Anne Frank "inappropriate".

The American actress was quizzed about Bieber’s comment as she walked the red carpet at the MTV Movie Awards last night.

Justin caused outrage after visiting Holocaust victim Anne Frank’s house in Amsterdam during the European leg of his tour over the weekend. It was revealed he'd written he hoped she would have "been a Belieber" in the guest book. The phrase is the nickname given to his ardent fans.

Despite the Twitter storm that has raged over the remark, Chloë was careful not come down too harshly on the young popstar.

“I very much respect Anne Frank and what she went through,” Chloë told ET. “[It] is a very serious situation and you know to make a joke of it sometimes is kind of inappropriate. At the same time you can kind of think of the angle, well you know, you’ve got to bring light into those dark situations.”

Justin's message in the museum's guestbook read: "Truly inspiring to be able to come here. Anne was a great girl. Hopefully she would have been a Belieber."

The museum later posted the message to Facebook which spurred an onslaught of commentary on Twitter.

Jewish Anne famously kept a diary of her life during the German occupation of the Netherlands in World War II. Her family went into hiding for two years but were eventually betrayed and sent to concentration camps, where Anne died in 1945 aged 15.