The former couple, who divorced in 2010, have two sons together – Mason, 10, and six-year-old Jake.
"There is no truth to the claims that Eddie has requested child support from Brandi now," a representative for the actor told People. "Nor will he ever request child support from his ex-wife. The notion is preposterous. This is yet another ploy for self-promotion."
Brandi and Eddie divorced in 2010
Eddie was responding to Brandi's public message on Twitter. The Real Housewives of Beverly Hills star had slammed her ex-husband for allegedly asking her to pay for child support, more than three years after their divorce was finalised.
"I'm not taking cheap shots at my ex in my new book cuz its all true, & now mr fancy new cars & house man is asking ME for child support! U know nada," wrote Brandi on Twitter.
The 41-year-old continued her rant, posting, "Every time I take 1 step frwd I get a lawyer's letter that takes me 3 steps back so when people say move on, I say 2 my ex LET ME! Just STOP."
An insider close to the situation explained the financial issue in more detail, telling People, "Now that Brandi is making money and is successful, Eddie is backtracking on a prior agreement they had regarding child support payments. He's asking for money back from her, over $100,000, saying he overpaid. But he's asking for more than he's paid her in the first place."
LeAnn Rimes and Eddie married in 2011
Brandi, who has just launched her latest book about dating and partying, recently revealed that she and her ex-husband were never "truly rich."
"We were ghetto rich," said Brandi. "We had the nice cars, the nice house, and the nice jewels, but we probably had a second and a third mortgage. We were living pay cheque to pay cheque, with no savings."
Eddie and Brandi's nine-year marriage broke down after the actor had an affair with his current wife LeAnn Rimes.
The 40-year-old star went public with his new relationship while he was still a married man. Eddie filed for divorce in 2009, citing "irreconcilable differences."
Two years later, Eddie and LeAnn married in an intimate ceremony in California, which had Eddie's two sons in attendance.