A 3,000-year-old bust of the famous boy king, who ruled Egypt from 1332 to 1323 B.C., is scheduled to be auctioned on July 4.
The quartzite statue, which portrays the boy king as Amun, the ancient Egyptian god of the sun and air, could generate more than $5 million, according to Christie's.
"The antiquities ministry has contacted the auction house and UNESCO to stop the procedures of selling the ancient artifact as well as demanding that [Christie's] provide the documents of the artifact's ownership," the foreign ministry said in a statement Monday.
"In addition, Egypt claims its right in the piece under the current and previous Egyptian laws."
The statue is expected to be sold by a private collector, and is part of what is known as the Resandro Collection, according to the Financial Times.
Egyptian officials introduced a law in 1983 to regulate the ownership of Egyptian antiquities, saying that any ancient artifacts discovered in the country are considered state properties "with the exception of antiquities whose ownership or possession was already established at the time this law came into effect."
"For its part, the Egyptian embassy in London contacted the British Foreign Office and the auction house to stop the sale ... and demand the return of the head to Egypt," Monday's statement read. "[The embassy] also demanded that the British side stop the sale of the rest of the Egyptian pieces to be sold at Christie's Hall on July 3-4, 2019, and obtain all of the ownership documents."
Zahi Hawass, a renowned Egyptian archaeologist who has spearheaded numerous campaigns to repatriate Egyptian artifacts, told ABC News in a recent interview that the statue was probably stolen from Luxor's Karnak Temple.
Christie's officials insisted the process was legal, saying in a statement that "ancient objects by their nature cannot be traced over millennia. It is hugely important to establish recent ownership and legal right to sell, which we have clearly done."
To mark the centenary of Tutankhamun's tomb discovery, Egypt earlier this year embarked on a world tour of 150 King Tut artifacts that include 60 pieces that have never left the country.
The exhibition kicked off in Paris in March and will move to locations around the world including London, California and Sydney until 2021.
A museum to house those artifacts and many others, the Grand Egyptian Museum, located near the Giza Pyramids, is currently under construction.