The third film in the Potter series opened in over 500 cinemas on 31 May, and took more than the first days of the first two films put together.

Meanwhile, author JK Rowling said it was her favourite Potter film so far.

Speaking on her website, jkrowling.com, she said: "I first saw Prisoner of Azkaban when it was barely finished. I loved it immediately."

She also praised the actors who play her creations on screen for keeping their feet on the ground.

She said: "They are the least egotisitical teenage actors you are ever likely to meet."

She went on to reveal she had been offered one of the giant inflatable Aunt Marges from outside the premiere.

"I thought it would have been more fun to untie them and let them drift over the country for the next couple of days," she said.