A previously unseen story written by children's author Beatrix Potter more than 100 years ago will be published in September.

The manuscript, titled The Tale Of Kitty-In-Boots, was discovered two years ago by publisher Jo Hanks.

The drawings for the story will be done by illustrator Quentin Blake, who worked on Roald Dahl's books.

Potter is best known for children's book The Tale Of Peter Rabbit, which was an instant success after being picked up in 1902 by publisher Frederick Warne & Co.

Hanks found a reference to The Tale Of Kitty-In-Boots in an out-of-print literary history about the author.

The book referenced a letter Potter sent her publisher in 1914, in which she mentioned the new tale and described it as being about "a well-behaved prime black Kitty cat, who leads rather a double life".

Blake said he liked the story instantly, adding: "I have a strange feeling that it might have been waiting for me."

Hanks, publisher of Beatrix Potter's works for Penguin Random House, said Blake was the perfect choice to illustrate the new tale because he "understands what makes a story engaging for children and adults, just as Potter did".

This year marks the 150th anniversary since Potter's birth.