Award-winning Nigerian writer, Chimamanda Ngozi Adichie has refuted claims by fellow author, Anne Giwa-Amu, that she plagiarized her Half of a Yellow Sun book.

The critically acclaimed book, which was published in 2006, received the prestigious Orange Prize for Fiction the following year and also garnered praises from Chinua Achebe and The New York Times.

Giwa-Amu, who is of Nigerian and Welsh heritage, shared a video on YouTube on Saturday claiming her book, Sade, which was published in 1996, was plagiarized by Adichie when she wrote Half of a Yellow Sun.

According to Giwa-Amu, she noticed the plagiarism and similarities between the two books in 2013 when she saw a poster in London advertising the movie adaptation for Half of a Yellow Sun.

“The poster depicted a love story between a mixed-race woman, played by Thandie Newton and an Igbo man, played by Chiwetel Ejiofor, set in Nigeria, Biafra” she said. “As this was the original story of ‘Sade,’ it provoked me to purchase a copy of ‘Half of a Yellow Sun’.”

She continued that she realized both of the book covers shared similarities after receiving it and alleged that upon reading Adichie’s book, she “discovered it was a rewrite of ‘Sade’.”

She further alleged that after her book was approved and published by Heinemann Education Books Nigeria in the West African country in 1999, Chinua Achebe, who was one of the board of directors of the publishing firm, contacted Adichie “who started to work on the infringing novel.”

Regarded as “the father of modern African literature”, Achebe is a well-known mentor of Adichie.

Adichie and her representatives, Wylie Agency, however, released a statement refuting those claims, calling them “libelous,” The Guardian Nigeria reports.

According to the statement, which claimed Adichie and publishers never knew about the book until the allegations were raised, Giwa-Amu’s claim of plagiarism was even dismissed by a court in the United Kingdom in 2019 when she brought the case against them.

They added that a professional independent reader who was ordered by the court to read both books “concluded that there was absolutely no basis for Giwa-Amu’s claim and advised that the claim should not be pursued.”

“On 15 February 2019, Anne Giwa-Amu’s claim brought against Chimamanda Ngozi Adichie and her publishers was struck out by the court. The court determined that her claim was ‘an abuse of the court’s process,” the statement read.

The statement also revealed Giwa-Amu was ordered by the court to pay Adichie and her publishers £14,250 ($16, 908) which she is yet to settle, alongside Adichie’s legal fees.

“Her present allegations are false, libellous and constitute a harassment to Chimamanda Ngozi Adichie. Further legal actions are being taken,” the statement said.