THERE’s a royal battle brewing between the future Queen of England and the King of Rock ’n’ Roll’s daughter – AND it’s GONNA GET UGLY!

Kate Middleton is furious that Lisa Marie Presley – who calls Great Britain home – is acting as though the British education system isn’t good enough for her 4-year-old twin daughters, say sources.

“Kate is livid that Lisa Marie refuses to send her children to an English preschool,” a source told The ENQUIRER. “She thinks it’s outrageous and certainly in poor taste that Lisa Marie lives in England, but doesn’t trust the country’s schools.

“She said if England is good enough for Lisa Marie and her family, then surely the educational programs should be perfectly adequate for her kids.”

The Duchess of Cambridge is so steamed, says the source, she’s told friends she wants Lisa Marie banned from any future royal functions!

Lisa Marie, 44, her musician/ producer husband Michael Lockwood, and their darling daughters, Harper Vivienne and Finley Aaron, enjoy the good life on a $14 million estate in the village of Rotherfield, East Sussex.

But Lisa Marie doesn’t want to keep with the British custom of sending the girls to school at 3, saying she would prefer to keep them home until they are 5 or 6.

“That’s the age they start in the States,” she noted during a recent interview. “I just don’t want to shove them off so early. I’m stunned when I see the age range. I don’t want to lose them that quick.”

According to sources, 30-year-old Kate, who’s become known as “The Children’s Princess” among the royal family, is hoping Lisa Marie changes her mind…for the twins’ sake.

“Kate knows things are done differently in the UK than the United States, but she’s convinced that children in England are more self-sufficient and capable than kids in America,” added the source. “Kate hopes someone persuades Lisa Marie to enroll her children in school early. And if she does, Kate will consider lifting the royal ban!”