A Frozen sequel is under way, Disney has announced.

Frozen became the highest-grossing animated film of all time in 2014.

The Oscar-winning animation made $1.27 billion at box offices worldwide, and led to record sales of related merchandise.

Frozen 2 will reunite the team behind the original feature, including director Chris Buck, writer Jennifer Lee and producer Peter Del Vecho.

The studio did not name a release date.

Shares in parent company Walt Disney were up by almost 4% following the news.

Toy-maker Mattel, which currently owns the license to sell Frozen products, saw its shares rise by almost 5%.

Last month, Disney credited the continuing success of toys based on Frozen for an “incredibly strong quarter”.

Net income rose 19% to $2.2 billion in the three-month period, with revenues up 9% to $13.4 billion – both figures better than forecast.

In December, Frozen became iTunes’ biggest-selling movie of all time, while the soundtrack sold more than any other album in the US in 2014.

Additionally, DVD and Blu-ray sales of the animation broke the three million mark on the first day of their release.

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