SUDDENLY svelte MIRANDA LAMBERT is caught up in a shocking “stomach stapling” scandal!

The 5-foot-4 country spitfire has long battled the bulge – ballooning up to 135 pounds earlier this year – and now sources say friends are wondering whether she owes her re­cent dramatic weight loss to secret gastric bypass surgery.

The singer unveiled her sex-sational new 105-pound figure at the Country Music Associa­tion Awards on Nov. 6. She wore a figure-flattering blue gown that helped to make her look slimmer than she really is, claimed sources who added that along with possible sur­gery, the gown alone made her seem to be cheating about her weight loss. However, she insists she achieved the amazing transformation thanks to good old-fashioned exercise and portion control.

“Miranda is bragging that she dropped 30 pounds in just three months,” divulged a close source.

“But up until mid-October, she still looked chubby and out of shape. Now there’s buzz swirling, even in Miranda’s camp, that she secretly had a stomach stapling operation. People are saying that’s the real reason for her sudden slim-down. Otherwise, the time­line of her weight loss claims just doesn’t add up.”

The “Mama’s Broken Heart” songbird claims that she dropped pounds by giving up her beloved Cheetos and eating vegetables, juicing and grazing on smaller portions of low-fat meat and fish.

“That sounds improba­ble,” scoffed the source. “All signs point to Miranda having secretly gone un­der the knife.”

Raising further flags about her weight loss, Miranda told a reporter: “I refuse to give up drinking,” claim­ing that she’s switched to low-calorie cocktails such as her “Mirandar­ita,” a custom blend of rum with raspberry lemonade – flavored Crystal Light and a splash of Sprite Zero.

The 30-year-old blonde also claims she’s devoting 70 minutes a day to exercise, including jogging in place and shadow-boxing. But just last year, she in­sisted: “I absolutely hate exercise.”

While Miranda has di­eted in the past, trying Atkins and doing Nutri­System a few times, “she’s a classic yo-yo dieter,” revealed the source.

“She’s never been able to maintain her weight losses. “Besides that, Miranda has made jokes about get­ting her stomach stapled, undergoing Lap-Band surgery and even having liposuction to get the fat sucked out of her.

“She’s the first to tell you that she’s never been able to win the battle of the bulge because she’s impatient and impulsive. That’s why lots of people think she turned to surgery for a quick fix.”

 As The ENQUIRER has reported, Miranda went on a “revenge diet” as payback against her skirt-chasing husband Blake Shelton and to attract young hunks.

She’s been fuming for months over the 37-year-old “Honey Bee” singer’s in­fatuation with slim, shapely women like pop star Chris­tina Aguilera, his fellow mentor on “The Voice” who also dropped 30 pounds re­cently.

Miranda and Blake’s three-year marriage has been strained since early last year when Miranda confronted singer Cady Groves, 24, whom she suspected of cheat­ing with her hubby.

She’s also warned Blake to stay away from Sea­son 3 “Voice” winner Cassadee Pope, 24. And she was said to have hit the roof when Blake was recently photographed getting cozy in an L.A. nightclub with 25-year-old aspiring actress Lindsey Sporrer.

Miranda’s ongoing jealousy has sparked fears that the couple could be headed toward a bitter $40 million divorce battle.

“Right now Miranda is under a ton of pressure, not only on a personal level to hold her marriage together, but also professionally,” said the source.

“She has a record coming out in the spring, and there’s talk that she’ll hit the road for a huge concert tour.

“Of course Miranda wants to look her best when she’s on the road and promoting her new music. But most of all, she’s been pulling out the stops to rescue her marriage.

“No one would be shocked to learn that she turned to surgery as a quick fix for her issues.”

The singer was up to 135 lbs earlier this year