Kevin Costner wants estranged wife to pay his legal fees after she challenged prenup

New court documents obtained by PEOPLE indicate that Kevin Costner, who is 68 years old, is requesting $99,225 in legal fees from his estranged wife, Christine. Costner claims that the expenses were related to their prenuptial agreement litigation.

The prenup states that if either party had counsel to "enforce or prevent a breach" of the agreement, "the prevailing party ... shall be entitled ... to be reimbursed by the non-prevailing party for all costs and expenses incurred thereby."

In a previous filing, his estranged wife and her team had asked him to pay their legal expenses, "Due to the vast difference in resources available to the parties, Christine is also requesting that Kevin advance an additional $350,000 in attorney’s fees and $150,000 in forensic costs."

Christine’s July 5 filing also questioned Kevin’s demand to have her pay his legal fees.

"Kevin asserts that he should not have to pay fees and costs for Christine to challenge the validity of the PMA [pre-marital agreement]. He also regularly claims that the PMA is valid and that there is no evidence to the contrary. This is the legal equivalent of whistling past the graveyard."

They continued, "As the Court can see by the pleadings at this early stage, the fees and costs will be substantial because Kevin’s finances are complex, and also because Kevin is doing all that he can to minimize his obligation to his children."