LIZA MINNELLI is smit­ten with two decades younger MATHHEW Mc­CONAUGHEY – and his fuming wife has ordered him to keep his distance.

The 67-year-old, four-times-divorced diva was so impressed by Matthew’s Golden Globe-win­ning performance in “Dallas Buy­ers Club” that she threw a private luncheon party for him and his cast mates at New York’s Monkey Bar in early January.

Beaming with adoration, Liza told the 44-year-old hunk: “Honey, if you don’t win the Oscar, I’ll give you mine!”

Just going out to see Matthew was a big deal for the troubled en­tertainer, who has been seen out less because of anxiety issues, a source says. In fact, although her reps claimed she never reached agreement on a script, Liza lost a $1 million payday when she refused to leave her apartment to do a cough drops commercial. Martha Stewart wound up filling in for her at the last minute and pocketed the dough.

But Liza had no qualms about venturing out to laud Matthew.

“Liza is a huge fan of ‘Dallas Buyers Club,’ but she’s definitely a bigger fan of Matt,” an insider told The ENQUIRER. “She’s a shameless flirt whenever she’s around him.

“And Matt played up to her. He grinned sheepishly and winked when­ever Liza gazed in his direction. She even made him blush.”

But the actor’s Brazilian model wife Camila, the mother of his three children, was none too happy with Matthew’s behavior toward Liza.

“Camila is not the jealous type, but Liza’s crush on Matt rubbed her the wrong way,” said the source. “She told him: ‘Come on, she’s old enough to be your mother!’”