Lawyers for the estate of Puzo also sought to end Paramount's rights to the 1969 best-seller, which went on to become an Oscar-winning movie released by the studio.

"Mario Puzo brought vast wealth to Paramount at a time when they desperately needed it. Now that he's gone, Paramount's trying to deprive his children of the rights he specifically reserved," Bertram Fields, an attorney for the Puzo family, said in a statement on Tuesday.

"I promised Mario I'd protect his kids from this kind of reprehensible conduct. Paramount wanted a war, and they're going to get one - only the stakes will be much higher than they thought," Fields added.

Paramount filed a lawsuit in Manhattan federal court in February that accused Puzo's heirs of approving sequels to "The Godfather" without the studio's permission and in violation of earlier agreements.

A third book "The Family Corleone" is due to be published in May. It is billed as an all-new prequel to "The Godfather" set in New York in 1933.

The counterclaim, filed on Monday, said Puzo's estate had informed Paramount several times of the upcoming publication of "The Family Corleone" and noted that the movie studio had not objected to the book "The Godfather's Revenge" in 2006.

Moreover, the estate said, Puzo received only "minimal payment" from Paramount for the rights to "The Godfather" and that the agreement at the time excluded rights to any further books that include the characters from "The Godfather" in new and different situations.

"The Puzo Estate, representing the children of Mario Puzo, needs no permission from Paramount to use the title of their father's novel or to publish a sequel novel or to use what Paramount claims are 'the Godfather works'," the counterclaim said.

Attorneys asked the court to terminate the rights of Paramount to the original "The Godfather" book and asked for $10 million in damages.

Paramount could not immediately be reached for comment on Tuesday.

Mario Puzo died in 1999. The two sequels to the story of the Corleone Mafia family that have been published since his death were written by U.S. author Mark Winegardner, and the forthcoming third novel is written by Ed Falco.

(Reporting By Jill Serjeant; Editing by Bob Tourtellotte)

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