BLAKE SHELTON may have handpicked Cher to men­tor his team on this season of “The Voice,” but it looks like that decision has turned out to be a HUGE mistake!

The conservative country crooner and the liberal “Woman’s World” sing­er are clashing so much that they’re barely on speaking terms, say sources.

“Cher wishes she never agreed to be Blake’s team mentor,” a set insider told The ENQUIRER. “She can’t stand him. She’s already called him a big jerk and told him how much she hated him.

“While she’s a fan of Blake’s musical talent, she can’t seem to get over his backwoods, country cowboy ways and his constant flirting with the sexier female singers on the show.”

Cher recently blew up at the “Hill­billy Bone” singer when he went on a long political rant about how Presi­dent Obama is “ruining the country.”

“Cher calmly tried to warn him to leave his politics at home, especially around the younger contestants,” said the source. “But then Blake tried to reason with her and said, ‘Listen, sweetheart…’”

And that’s when Cher apparently lost it.

“She called him a jerk and said he was ‘nothing but a dumb cowboy,’ ” the source divulged. “Blake retaliated and called her a ‘typical Hollywood liberal,’ and that’s when she really went off, yelling, ‘I hate you!’”

Blake, 37, whose singers have won the last three seasons of “The Voice,” admitted that he and Cher have had their differences.

“I don’t know if she likes me that much,” the staunch Republican and supporter of former President George W. Bush recently said on “Live with Kelly & Michael.”

And 67-year-old Cher, who just released her 26th studio album, “Closer to the Truth,” was labeled trouble before she even set foot on the set.

As The ENQUIRER exclusively re­ported in our Sept. 30 issue, Blake’s wife, Miranda Lambert, warned her badboy hubby to stay away from Cher, calling the Oscar winner a “cougar.”

Cher, who has a history of dating younger men, laughed when she heard about Miranda’s warning. But she blasted back, telling the crew that while she may be a cougar she’s “certainly not a cheater.”

According to the source, Blake and Cher may not like each other, but they still want their singers to win the “The Voice.”

“Cher may respect Blake’s ability to mold talent, but that doesn’t mean she has to like him as a person,” the source added. “They’ve both been very clear about not wanting to spend any more time together than they have to.

“It’s a mutual hate-hate relationship, and it’ll be interesting to watch Blake and Cher try to work together. Hope­fully they won’t tear each other’s heads off.”