Kevin Costner 'does not know' whether ex-wife Christine Baumgartner had affairs

Kevin Costner has questioned whether his ex-wife Christine Baumgartner had extramarital affairs.

According to court documents obtained by Us Weekly on Thursday, the Yellowstone star has responded to his ex-wife's request for financial documents by speculating on the possibility that she cheated on him during their marriage.

Lawyers for Costner, 68, wrote that he couldn't provide any requested financial documents "relating to extramarital romantic relationships" because they did not exist, as he did not engage in an affair while married to Baumgartner.

The actor's lawyers slammed the financial documents request for being "propounded only for purposes of harassment" and "overbroad as to time period and subject matter, burdensome, oppressive and impermissibly compound".

They also noted that Costner "does not know for a fact if (Baumgartner) engaged in any 'extramarital romantic relationships' before separation and, if so, whether she spent any of his money or charged any expenses in furtherance of her affair(s) on credit cards he paid".

Baumgartner, 49, claimed in a Monday filing that Costner was "stonewalling" the divorce process by refusing to release certain documents before their next child support hearing.

In addition to requesting financial documents related to extramarital relationships, Baumgartner's legal team requested receipts regarding Costner's living expenses, savings accounts, retirement accounts, and others. Costner has claimed these documents were "not relevant" to their divorce proceedings.

The television star has also claimed that financial documents regarding his upcoming four-part film saga Horizon were irrelevant to the proceedings, citing their prenuptial agreement. The agreement stated, "All income earned during marriage would be the separate property of the spouse earning the income and providing for no community property."

The pair have been set to determine the validity of their prenuptial agreement in a November trial.

Baumgartner filed for divorce from Costner in May after 18 years of marriage. The pair share three children.