BRITNEY SPEARS has vowed not to waste a single minute on another dead-end rela­tionship – and she’s slapped new beau David Lucado with a baby and marriage ultimatum.  

Incredibly, it worked!

Although they’ve been dating for less than three months, sources say David, 27, has given his pop sweetheart an informal engagement ring.

BRITNEY, 31, announced in January that she and her agent, fiancé Jason Trawick, had split up. Although insiders say she’s moved on, the “Scream & Shout” singer feels like she wasted nearly four years waiting for him to marry her and start a family.

“She refuses to fall into that trap again with her new guy,” said a source. “Britney told David she wants a firm commitment that he wants to marry and give her a child – or get out of her life for good. To Britney’s surprise, David presented her with a modest gold ring to prove he’s totally com­mitted to her.”

In a recent inter­view with “Extra” host Mario Lopez, Britney didn’t make any bones about her desire to have another child, declaring: “I want a baby girl.”

Meanwhile, the former “X Factor” judge was pictured in Thousand Oaks, Calif., on May 11 flaunting the ring. “David is planning a more formal engagement with Britney later this year, but he wanted to give her something now to show her he’s in this relationship for the long haul,” the source said.

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