A UK mum has slammed her “useless” ex-partner for failing to pay child support in a scathing, 1300-word open letter on Facebook.

The unidentified woman, posting under the name Single Mum Still Standing, accused the “rubbish father” of under-declaring his income to authorities to avoid paying her the required 16 per cent, while telling her to “go out less” when challenged.

“Any child maintenance payments made by you to me do not pay for my holidays,” she wrote in the post, which has been shared more than 6000 times.

“I don’t use YOUR money to pay for my clothes, and your payments certainly don’t fund my minor prosecco addiction. Your hard-earned cash doesn’t help me pay my gym membership or go into my savings account. (Which doesn’t exist.)

“So when you stalk my Instagram and Facebook and see me making the most of my child-free weekends with friends — rest assured I am funding this. In the words of Destiny’s Child, ‘The shoes on my feet, I bought ‘em — I depend on me, if I want it.’

“Let me spell this out for you — any money you pay to help with the raising of our children goes directly to our children. I’ve got two jobs to fund my own lifestyle and pay for our children. It’s a simple concept you don’t seem to be able to grasp.”

The woman said child support payments went towards her mortgage, “the house which puts a roof over our children’s heads”, put clothes on their backs, shoes on their feet, paid for swimming lessons and birthday presents.

“The Child Maintenance Service [orders] you an amount to pay based on the amount YOU have declared to them — but the small wage you pay yourself is not a true reflection of what you actually earn,” she wrote.

“You’re just so clever — exploiting a loophole to financially abuse our children ... All I know is that I am trying to provide a life which is similar to what they would have had if you and I had not split up. You failing to pay is just another parenting fail.”

The post has attracted nearly 3000 comments, with many sympathising with the mum. “Couldn’t have said it better myself,” wrote Michelle Wright.

“I go through this every day too. My now ex-husband didn’t even buy one present for our three children at Christmas and yet he owns half of an estate agency. So it’s not down to money issues, just cannot be bothered.”

Lisa Paz added, “Well bloody said! Makes me so mad. I literally work for nothing, while he has everything and doesn’t pay out of spite ... to make me look like the p**s poor parent while he flashes his cash at them.”

Mark Spence said he had “paid every day” since his son was born and didn’t understand why someone wouldn’t. “It’s not the kids’ fault that parents don’t get on anymore, why should the kids suffer?” he wrote.

Others pointed out that it wasn’t always the fathers. “Women are just as bad for this too,” wrote Dan Pickett. “I’ve had full custody of my kids since they were three and nine months and have never received a single penny off their mother. She also hasn’t seen them or spoken to them in eight years.”